diff --git a/.gitignore b/.gitignore
index db4ed747c..9ff16b94c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -17,6 +17,7 @@ build/VC2010
 # Sphinx generated documentation
 docs/_*
 docs/html/
+docs/pdf/
 
 # in-place build
 build/Makefile
diff --git a/conf.py b/conf.py
index a46039126..d6c40b0a7 100644
--- a/conf.py
+++ b/conf.py
@@ -359,3 +359,5 @@ latex_documents = [
     (master_doc, 'DFHack.tex', 'DFHack Documentation',
      'The DFHack Team', 'manual'),
 ]
+
+latex_toplevel_sectioning = 'part'
diff --git a/docs/Documentation.rst b/docs/Documentation.rst
index 462932b0f..37fcc6ee6 100644
--- a/docs/Documentation.rst
+++ b/docs/Documentation.rst
@@ -236,9 +236,9 @@ Running Sphinx manually
 -----------------------
 
 You can also build the documentation without going through CMake, which may be
-faster. There is a ``docs/build.sh`` script available for Linux and macOS that
+faster. There is a ``docs/build.sh`` script provided for Linux and macOS that
 will run essentially the same command that CMake runs - see the script for
-options.
+additional options.
 
 To build the documentation with default options, run the following command from
 the root DFHack folder::
@@ -248,6 +248,19 @@ the root DFHack folder::
 Sphinx has many options to enable clean builds, parallel builds, logging, and
 more - run ``sphinx-build --help`` for details.
 
+Building a PDF version
+----------------------
+
+ReadTheDocs automatically builds a PDF version of the documentation (available
+under the "Downloads" section when clicking on the release selector). If you
+want to build a PDF version locally, you will need ``pdflatex``, which is part
+of a TeX distribution. The following command will then build a PDF, located in
+``docs/pdf/latex/DFHack.pdf``, with default options::
+
+  sphinx-build -M latexpdf . ./docs/pdf
+
+There is a ``docs/build-pdf.sh`` script provided for Linux and macOS that runs
+this command for convenience - see the script for additional options.
 
 .. _build-changelog:
 
diff --git a/docs/Lua API.rst b/docs/Lua API.rst
index 4c7163623..2cfaff350 100644
--- a/docs/Lua API.rst	
+++ b/docs/Lua API.rst	
@@ -158,7 +158,9 @@ that don't fit any of the other reference types. Such
 references can only appear as a value of a pointer field,
 or as a result of calling the ``_field()`` method.
 
-They behave as structs with one field ``value`` of the right type.
+They behave as structs with a ``value`` field of the right type. If the
+object's XML definition has a ``ref-target`` attribute, they will also have
+a read-only ``ref_target`` field set to the corresponding type object.
 
 To make working with numeric buffers easier, they also allow
 numeric indices. Note that other than excluding negative values
diff --git a/docs/build-pdf.sh b/docs/build-pdf.sh
new file mode 100755
index 000000000..76908b49b
--- /dev/null
+++ b/docs/build-pdf.sh
@@ -0,0 +1,23 @@
+#!/bin/sh
+
+# usage:
+#   ./build-pdf.sh
+#   SPHINX=/path/to/sphinx-build ./build-pdf.sh
+#   JOBS=3 ./build-pdf.sh ...
+# all command-line arguments are passed directly to sphinx-build - run
+# ``sphinx-build --help`` for a list, or see
+# https://www.sphinx-doc.org/en/master/man/sphinx-build.html
+
+cd $(dirname "$0")
+cd ..
+
+sphinx=sphinx-build
+if [ -n "$SPHINX" ]; then
+    sphinx=$SPHINX
+fi
+
+if [ -z "$JOBS" ]; then
+    JOBS=2
+fi
+
+"$sphinx" -M latexpdf . ./docs/pdf -w ./docs/_sphinx-warnings.txt -j "$JOBS" "$@"
diff --git a/docs/build.sh b/docs/build.sh
index 48e1bfd4a..95a97e539 100755
--- a/docs/build.sh
+++ b/docs/build.sh
@@ -1,9 +1,12 @@
 #!/bin/sh
 
 # usage:
-# ./build.sh
-# ./build.sh sphinx-executable
-# JOBS=3 ./build.sh ...
+#   ./build.sh
+#   SPHINX=/path/to/sphinx-build ./build.sh
+#   JOBS=3 ./build.sh ...
+# all command-line arguments are passed directly to sphinx-build - run
+# ``sphinx-build --help`` for a list, or see
+# https://www.sphinx-doc.org/en/master/man/sphinx-build.html
 
 cd $(dirname "$0")
 cd ..
@@ -17,4 +20,4 @@ if [ -z "$JOBS" ]; then
     JOBS=2
 fi
 
-"$sphinx" -a -E -b html . ./docs/html -w ./docs/_sphinx-warnings.txt -j "$JOBS" "$@"
+"$sphinx" -a -b html . ./docs/html -w ./docs/_sphinx-warnings.txt -j "$JOBS" "$@"
diff --git a/docs/changelog.txt b/docs/changelog.txt
index e43abd188..8ce2fa683 100644
--- a/docs/changelog.txt
+++ b/docs/changelog.txt
@@ -37,6 +37,7 @@ changelog.txt uses a syntax similar to RST, with a few special sequences:
 - Fixed a segfault when attempting to start a headless session with a graphical PRINT_MODE setting
 - Fixed an issue with the macOS launcher failing to un-quarantine some files
 - `labormanager`: fixed handling of new jobs in 0.47
+- `embark-assistant`: fixed a couple of incursion handling bugs.
 - Fixed ``Units::isEggLayer``, ``Units::isGrazer``, ``Units::isMilkable``, ``Units::isTrainableHunting``, ``Units::isTrainableWar``, and ``Units::isTamable`` ignoring the unit's caste
 - `RemoteFortressReader`: fixed a couple crashes that could result from decoding invalid enum items (``site_realization_building_type`` and ``improvement_type``)
 
@@ -45,6 +46,9 @@ changelog.txt uses a syntax similar to RST, with a few special sequences:
 - `blueprint`: now automatically creates folder trees when organizing blueprints into subfolders (e.g. ``blueprint 30 30 1 rooms/dining dig`` will create the file ``blueprints/rooms/dining-dig.csv``); previously it would fail if the ``blueprints/rooms/`` directory didn't already exist
 - `confirm`: added a confirmation dialog for convicting dwarves of crimes
 
+## Lua
+- Added a ``ref_target`` field to primitive field references, corresponding to the ``ref-target`` XML attribute
+
 ## Ruby
 - Updated ``item_find`` and ``building_find`` to use centralized logic that works on more screens
 
diff --git a/docs/styles/dfhack.css b/docs/styles/dfhack.css
index daedd1120..a25772871 100644
--- a/docs/styles/dfhack.css
+++ b/docs/styles/dfhack.css
@@ -56,3 +56,8 @@ div.sphinxsidebar h3.logo-name a {
 div.body {
     min-width: unset;
 }
+
+div.body li > p {
+    margin-top: 0;
+    margin-bottom: 0;
+}
diff --git a/library/LuaTypes.cpp b/library/LuaTypes.cpp
index c46d7ce05..845d273e3 100644
--- a/library/LuaTypes.cpp
+++ b/library/LuaTypes.cpp
@@ -536,6 +536,7 @@ static void field_reference(lua_State *state, const struct_field_info *field, vo
         case struct_field_info::PRIMITIVE:
         case struct_field_info::SUBSTRUCT:
             push_object_internal(state, field->type, ptr);
+            get_object_ref_header(state, -1)->field_info = field;
             return;
 
         case struct_field_info::POINTER:
@@ -706,6 +707,17 @@ static type_identity *find_primitive_field(lua_State *state, int field, const ch
  */
 static int meta_primitive_index(lua_State *state)
 {
+    const char *attr = lua_tostring(state, -1);
+    if (strcmp(attr, "ref_target") == 0) {
+        const struct_field_info *field_info = get_object_ref_header(state, 1)->field_info;
+        if (field_info && field_info->extra && field_info->extra->ref_target) {
+            LookupInTable(state, field_info->extra->ref_target, &DFHACK_TYPEID_TABLE_TOKEN);
+        } else {
+            lua_pushnil(state);
+        }
+        return 1;
+    }
+
     uint8_t *ptr = get_object_addr(state, 1, 2, "read");
     auto type = find_primitive_field(state, 2, "read", &ptr);
     if (!type)
@@ -1304,6 +1316,8 @@ static void MakePrimitiveMetatable(lua_State *state, type_identity *type)
     {
         EnableMetaField(state, base+2, "value", type);
         AssociateId(state, base+3, 1, "value");
+
+        EnableMetaField(state, base+2, "ref_target", NULL);
     }
 
     // Add the iteration metamethods
diff --git a/library/LuaWrapper.cpp b/library/LuaWrapper.cpp
index 497addd5c..05c4db789 100644
--- a/library/LuaWrapper.cpp
+++ b/library/LuaWrapper.cpp
@@ -170,18 +170,24 @@ void LuaWrapper::push_object_ref(lua_State *state, void *ptr)
     // stack: [metatable]
     auto ref = (DFRefHeader*)lua_newuserdata(state, sizeof(DFRefHeader));
     ref->ptr = ptr;
+    ref->field_info = NULL;
 
     lua_swap(state);
     lua_setmetatable(state, -2);
     // stack: [userdata]
 }
 
-void *LuaWrapper::get_object_ref(lua_State *state, int val_index)
+DFRefHeader *LuaWrapper::get_object_ref_header(lua_State *state, int val_index)
 {
     assert(!lua_islightuserdata(state, val_index));
 
     auto ref = (DFRefHeader*)lua_touserdata(state, val_index);
-    return ref->ptr;
+    return ref;
+}
+
+void *LuaWrapper::get_object_ref(lua_State *state, int val_index)
+{
+    return get_object_ref_header(state, val_index)->ptr;
 }
 
 /**
diff --git a/library/include/LuaWrapper.h b/library/include/LuaWrapper.h
index 4cbf9d34f..b23e1f912 100644
--- a/library/include/LuaWrapper.h
+++ b/library/include/LuaWrapper.h
@@ -126,6 +126,7 @@ namespace LuaWrapper {
      */
     struct DFRefHeader {
         void *ptr;
+        const struct_field_info *field_info;
     };
 
     /**
@@ -133,15 +134,7 @@ namespace LuaWrapper {
      */
     void push_object_ref(lua_State *state, void *ptr);
     DFHACK_EXPORT void *get_object_ref(lua_State *state, int val_index);
-
-    /*
-     * The system might be extended to carry some simple
-     * objects inline inside the reference buffer.
-     */
-    inline bool is_self_contained(DFRefHeader *ptr) {
-        void **pp = &ptr->ptr;
-        return **(void****)pp == (pp + 1);
-    }
+    DFHACK_EXPORT DFRefHeader *get_object_ref_header(lua_State *state, int val_index);
 
     /**
     * Report an error while accessing a field (index = field name).
diff --git a/library/xml b/library/xml
index b9028b0bb..2c21bf250 160000
--- a/library/xml
+++ b/library/xml
@@ -1 +1 @@
-Subproject commit b9028b0bb9ad40d3ad4dc3f10934bb61aa16629b
+Subproject commit 2c21bf2503751fae87cfd62e9608003b5f0dc1c5
diff --git a/plugins/embark-assistant/defs.h b/plugins/embark-assistant/defs.h
index 29c5a063c..13494b91e 100644
--- a/plugins/embark-assistant/defs.h
+++ b/plugins/embark-assistant/defs.h
@@ -119,6 +119,8 @@ namespace embark_assist {
             df::world_region_type region_type[16][16];  //  Required for incursion override detection. We could store only the
                                                 //  edges, but storing it for every tile allows for a unified fetching
                                                 //  logic.
+            int8_t north_row_biome_x[16];    //  "biome_x" data cached for the northern row for access from the north.
+            int8_t west_column_biome_y[16];  //  "biome_y" data cached for the western row for access from the west.
         };
 
         struct geo_datum {
diff --git a/plugins/embark-assistant/survey.cpp b/plugins/embark-assistant/survey.cpp
index 79c66e4df..2d5dca04d 100644
--- a/plugins/embark-assistant/survey.cpp
+++ b/plugins/embark-assistant/survey.cpp
@@ -1470,6 +1470,8 @@ void embark_assist::survey::survey_mid_level_tile(embark_assist::defs::geo_data
 
         tile->north_corner_selection[i] = world_data->region_details[0]->edges.biome_corner[i][0];
         tile->west_corner_selection[i] = world_data->region_details[0]->edges.biome_corner[0][i];
+        tile->north_row_biome_x[i] = world_data->region_details[0]->edges.biome_x[i][0];
+        tile->west_column_biome_y[i] = world_data->region_details[0]->edges.biome_y[0][i];
     }
 
     for (uint8_t i = 0; i < 16; i++) {
@@ -1601,7 +1603,7 @@ df::world_region_type embark_assist::survey::region_type_of(embark_assist::defs:
     int16_t effective_y = y;
     int8_t effective_i = i;
     int8_t effective_k = k;
-    adjust_coordinates(&effective_x, &effective_y, &effective_i, &effective_i);
+    adjust_coordinates(&effective_x, &effective_y, &effective_i, &effective_k);
 
     if (effective_x < 0 ||
         effective_x >= world_data->world_width ||
@@ -1657,7 +1659,7 @@ uint8_t  embark_assist::survey::translate_corner(embark_assist::defs::world_tile
         effective_k = k + 1;
     }
 
-    adjust_coordinates(&effective_x, &effective_y, &effective_i, &effective_i);
+    adjust_coordinates(&effective_x, &effective_y, &effective_i, &effective_k);
 
     if (effective_x == world_data->world_width) {
         if (effective_y == world_data->world_height) {  //  Only the SE corner of the SE most tile of the world can reference this.
@@ -1919,7 +1921,17 @@ uint8_t embark_assist::survey::translate_ns_edge(embark_assist::defs::world_tile
         north_region_type = embark_assist::survey::region_type_of(survey_results, x, y, i, k - 1);
     }
     else {
-        effective_edge = world_data->region_details[0]->edges.biome_x[i][k + 1];
+        if (k < 15) {  //  We're still within the same world tile
+            effective_edge = world_data->region_details[0]->edges.biome_x[i][k + 1];
+        }
+        else {  //  Getting the data from the world tile to the south
+            if (y + 1 == world_data->world_height) {
+                return 4;  //  There's nothing to the south, so we fall back on our own tile.
+            }
+
+            effective_edge = survey_results->at(x).at(y + 1).north_row_biome_x[i];
+        }
+
         north_region_type = embark_assist::survey::region_type_of(survey_results, x, y, i, k);
         south_region_type = embark_assist::survey::region_type_of(survey_results, x, y, i, k + 1);
     }
@@ -1993,7 +2005,16 @@ uint8_t embark_assist::survey::translate_ew_edge(embark_assist::defs::world_tile
         west_region_type = embark_assist::survey::region_type_of(survey_results, x, y, i - 1, k);
     }
     else {
-        effective_edge = world_data->region_details[0]->edges.biome_y[i + 1][k];
+        if (i < 15) {  //  We're still within the same world tile
+            effective_edge = world_data->region_details[0]->edges.biome_y[i + 1][k];
+        }
+        else {  //  Getting the data from the world tile to the east
+            if (x + 1 == world_data->world_width) {
+                return 4;  //  There's nothing to the east, so we fall back on our own tile.
+            }
+
+            effective_edge = survey_results->at(x + 1).at(y).west_column_biome_y[k];
+        }
         west_region_type = embark_assist::survey::region_type_of(survey_results, x, y, i, k);
         east_region_type = embark_assist::survey::region_type_of(survey_results, x, y, i + 1, k);
     }
@@ -2424,7 +2445,7 @@ void embark_assist::survey::survey_embark(embark_assist::defs::mid_level_tiles *
         }
         else {
             process_embark_incursion_mid_level_tile
-            (translate_ns_edge(survey_results,
+            (translate_ew_edge(survey_results,
                 true,
                 x,
                 y,
@@ -2481,7 +2502,7 @@ void embark_assist::survey::survey_embark(embark_assist::defs::mid_level_tiles *
         }
         else {
             process_embark_incursion_mid_level_tile
-            (translate_ns_edge(survey_results,
+            (translate_ew_edge(survey_results,
                 false,
                 x,
                 y,
diff --git a/scripts b/scripts
index e8de92efb..af749e708 160000
--- a/scripts
+++ b/scripts
@@ -1 +1 @@
-Subproject commit e8de92efb73d5ef4d0b52df000d60d3350f07a37
+Subproject commit af749e7086739a058cd5095a6ee1a60d7e795a7c
diff --git a/test/main.lua b/test/main.lua
index 46a91e1ca..83a35d165 100644
--- a/test/main.lua
+++ b/test/main.lua
@@ -69,6 +69,19 @@ function expect.error(func, ...)
         return true
     end
 end
+function expect.error_match(func, matcher, ...)
+    local ok, err = pcall(func, ...)
+    if ok then
+        return false, 'no error raised by function call'
+    elseif type(matcher) == 'string' then
+        if not tostring(err):match(matcher) then
+            return false, ('error "%s" did not match "%s"'):format(err, matcher)
+        end
+    elseif not matcher(err) then
+        return false, ('error "%s" did not satisfy matcher'):format(err)
+    end
+    return true
+end
 function expect.pairs_contains(table, key, comment)
     for k, v in pairs(table) do
         if k == key then
diff --git a/test/structures/ref_target.lua b/test/structures/ref_target.lua
new file mode 100644
index 000000000..05818ee06
--- /dev/null
+++ b/test/structures/ref_target.lua
@@ -0,0 +1,35 @@
+function test.get()
+    dfhack.with_temp_object(df.unit:new(), function(unit)
+        expect.eq(unit:_field('hist_figure_id').ref_target, df.historical_figure)
+    end)
+end
+
+function test.get_nil()
+    dfhack.with_temp_object(df.coord:new(), function(coord)
+        expect.nil_(coord:_field('x').ref_target)
+    end)
+end
+
+function test.get_non_primitive()
+    dfhack.with_temp_object(df.unit:new(), function(unit)
+        expect.error_match(function()
+            return unit:_field('status').ref_target
+        end, 'not found')
+    end)
+end
+
+function test.set()
+    dfhack.with_temp_object(df.unit:new(), function(unit)
+        expect.error_match(function()
+            unit:_field('hist_figure_id').ref_target = df.coord
+        end, 'builtin property or method')
+    end)
+end
+
+function test.set_non_primitive()
+    dfhack.with_temp_object(df.unit:new(), function(unit)
+        expect.error_match(function()
+            unit:_field('status').ref_target = df.coord
+        end, 'not found')
+    end)
+end