diff --git a/README.md b/README.md
index 36a4170..581fe2a 100644
--- a/README.md
+++ b/README.md
@@ -31,3 +31,6 @@ Change appearance of questions and answers by hacking the files `qquestions.css`
 
 Here is the source code for a minimal example: [example.qmd](example.qmd).
 
+## Quirks
+
+In book projects, questions are numbered accross chapters. The way it is done now (v0.2.0) gives funny results in the previewer, but works well when rendering the whole project at once.
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diff --git a/_extensions/qquestion/_extension.yml b/_extensions/qquestion/_extension.yml
index b650e31..e7a8538 100644
--- a/_extensions/qquestion/_extension.yml
+++ b/_extensions/qquestion/_extension.yml
@@ -1,6 +1,6 @@
 title: qquestion
 author: Ute Hahn
-version: 0.1.0
+version: 0.2.0
 quarto-required: ">=1.4.0"
 contributes:
   filters:
diff --git a/_extensions/qquestion/qquestion.lua b/_extensions/qquestion/qquestion.lua
index decfb47..916b4f4 100644
--- a/_extensions/qquestion/qquestion.lua
+++ b/_extensions/qquestion/qquestion.lua
@@ -1,28 +1,67 @@
 -- nice rename function learned from shafayetShafee :-)
 -- local str = pandoc.utils.stringify
--- local pout = quarto.log.output
+local pout = quarto.log.output
 
--- important quasi global variables
+-- initiate rendering information and global question number
+local utelz = require("./utels")
+local rinfo = {}
 
-local ishtml = quarto.doc.is_format("html")
-local ispdf = quarto.doc.is_format("pdf")
-local qnum = 0
+-- initialize qnum, store and retrieve
+
+local function readqnum(renderinfo)
+  local file = io.open(renderinfo.qnumstore,"r")
+  local qnum = 0
+  if file then 
+    local qnumjson = file:read "*a"
+    file:close()
+    if qnumjson 
+       then qnum = quarto.json.decode(qnumjson)
+    end
+  end  
+  -- pout("got qnum as "..qnum)
+  -- pout(rinfo)
+  return(qnum)
+end;  
+
+local function store_qnum(renderinfo)
+  local qnjson = quarto.json.encode(renderinfo.qnum)
+  local file = io.open(renderinfo.qnumstore,"w")
+  if file ~= nil then 
+    file:write(qnjson) 
+    file:close()
+  end
+end
+ 
+function init_qnum(renderinfo)
+  if renderinfo.ishtmlbook then 
+    if renderinfo.isfirst then 
+      renderinfo.qnum = 0
+    else
+      renderinfo.qnum = readqnum(renderinfo)
+    end
+  else
+    renderinfo.qnum = 0    
+  end  
+end  
+
+-- functions for rendering
 
 local function qstart()
-  qnum = qnum+1
-  if ishtml then
-    return pandoc.RawInline("html",'🤔<sub>[Q'..qnum..']</sub><span class="qquestion" number='..qnum..'>')
-  elseif ispdf then 
-    return pandoc.RawInline("tex",'\\qquestion{'..qnum.."}{")
+  rinfo.qnum = rinfo.qnum+1
+  -- pout("qstart "..rinfo.qnum)
+  if rinfo.ishtml then
+    return pandoc.RawInline("html",'🤔<sub>[Q'..rinfo.qnum..']</sub><span class="qquestion" number='..rinfo.qnum..'>')
+  elseif rinfo.ispdf then 
+    return pandoc.RawInline("tex",'\\qquestion{'..rinfo.qnum.."}{")
   else
     return pandoc.Str("<QStart>")  
   end
 end  
 
 local function qend()
-  if ishtml then
+  if rinfo.ishtml then
     return pandoc.RawInline("html",'</span>')
-  elseif ispdf then 
+  elseif rinfo.ispdf then 
     return pandoc.RawInline("tex",'}')
   else
     return pandoc.Str("<QEnde>")  
@@ -30,10 +69,10 @@ local function qend()
 end  
 
 local function qans()
-  if ishtml then
-    return pandoc.RawInline("html",'</span><span class="qanswer" number='..qnum..'>')
-  elseif ispdf then 
-    return pandoc.RawInline("tex",'}\\qanswer{'..qnum.."}{")
+  if rinfo.ishtml then
+    return pandoc.RawInline("html",'</span><span class="qanswer" number='..rinfo.qnum..'>')
+  elseif rinfo. ispdf then 
+    return pandoc.RawInline("tex",'}\\qanswer{'..rinfo.qnum.."}{")
   else
     return pandoc.Str("<QEnde><QAnswer>")  
   end
@@ -42,7 +81,7 @@ end
 
 -- find {?? bla ??}
 
-Inlines = function(el)
+function Inlines_parse(el)
   for i,ele in pairs(el) do
     if ele.t == "Str" then 
       if ele.text == "{??" then
@@ -59,20 +98,41 @@ Inlines = function(el)
 end
 
 
--- TODO: book, save number between processed files? 
-
-Pandoc = function(doc)
-  if ishtml
+function Pandoc_doit(doc)
+  if rinfo.ishtml
   then 
     quarto.doc.add_html_dependency({
       name = 'qqstyle',
       stylesheets = {'qquestion.css'}
     })
-   elseif ispdf
+   elseif rinfo.ispdf
     then
       quarto.doc.use_latex_package("tcolorbox")
       quarto.doc.include_file('before-body','qquestion.tex')
       quarto.doc.add_format_resource("Emo_think.png")
   end
+ 
+  -- pout("yeah, still have to store qnum "..rinfo.qnum)
+  store_qnum(rinfo)
   return(doc)
-end  
\ No newline at end of file
+end  
+
+
+return{
+{ -- first get rendering information
+  Meta = function(meta) 
+    rinfo = utelz.Meta_getinfo(meta)
+    rinfo.qnumstore = "_qnumstore.json"
+    init_qnum(rinfo)
+   -- pout("render info ")
+   -- pout("==== book render info ==")
+   -- pout(meta.book.render)
+   -- pout("==== book chapter info ==")
+   -- pout(meta.book.chapters)
+  end  
+},
+{
+  Inlines = Inlines_parse,
+  Pandoc = Pandoc_doit
+}
+}
diff --git a/_extensions/qquestion/utels.lua b/_extensions/qquestion/utels.lua
new file mode 100644
index 0000000..ef6be35
--- /dev/null
+++ b/_extensions/qquestion/utels.lua
@@ -0,0 +1,75 @@
+
+local str = pandoc.utils.stringify
+local pout = quarto.log.output
+
+-- rendering information
+
+local function chapterinfo(book, fname)
+    local first = "" 
+    local last = "" 
+    local chapno = nil
+    local info = {}
+    --if book.render then
+      for _, v in pairs(book.render) do
+        if str(v.type) == "chapter" then
+          last = pandoc.path.split_extension(str(v.file))
+          if first == "" then first = last end
+          if last == fname then chapno = v.number end
+        end
+      end
+      info.islast = (fname == last)
+      info.isfirst = (fname == first)
+      info.lastchapter = last
+      info.chapno = chapno
+     -- pout("chapter inf:", info)
+      return(info)
+  end
+
+
+local function Meta_getinfo(meta)
+    local processedfile = pandoc.path.split_extension(PANDOC_STATE.output_file)
+    local ispdf, ishtml, isbook, ishtmlbook = false, false, false, false
+    local rinfo={}
+
+    -- pout("here we go")
+    rinfo.ispdf = quarto.doc.is_format("pdf")
+    rinfo.ishtml = quarto.doc.is_format("html")
+    rinfo.isbook = meta.book ~=nil
+    rinfo.ishtmlbook = rinfo.isbook and rinfo.ishtml
+      
+    rinfo.processedfile = processedfile
+    rinfo.output_file = PANDOC_STATE.output_file
+   -- pout(" now in "..processedfile.." later becomes ".. str(fbx.output_file))
+    
+    rinfo.isfirst = not rinfo.ishtmlbook
+    rinfo.islast = not rinfo.ishtmlbook
+    if rinfo.isbook then 
+      local chinfo = chapterinfo(meta.book, processedfile)
+      rinfo.isfirst = chinfo.isfirst 
+      rinfo.islast = chinfo.islast
+      if meta.chapno then  
+        rinfo.chapno = str(meta.chapno)
+      else
+        if chinfo.chapno ~= nil then
+          rinfo.chapno = str(chinfo.chapno)
+        else  
+          rinfo.chapno = ""
+          rinfo.unnumbered = true
+        end
+      end
+    else -- not a book. 
+      rinfo.chapno = ""
+      rinfo.unnumbered = true
+    end
+    --pout(rinfo)
+    return(rinfo)
+  end
+
+
+--[[ 
+--]]
+return {
+    Meta_getinfo = Meta_getinfo
+}  
+--[[ 
+--]]
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