See http://orgmode.org/manual/Include-files.html
% pandoc -f org -t native
Text
#+include: "command/3510-subdoc.org"
#+INCLUDE: "command/3510-src.hs" src haskell
#+INCLUDE: "command/3510-export.latex" export latex
More text
^D
[Para [Str "Text"]
,Header 1 ("subsection",[],[]) [Str "Subsection"]
,Para [Str "Included",Space,Str "text"]
,Plain [Str "Lorem",Space,Str "ipsum."]
,CodeBlock ("",["haskell"],[]) "putStrLn outString\n"
,RawBlock (Format "latex") "\\emph{Hello}"
,Para [Str "More",Space,Str "text"]]