session "Lex" = HOL +
  theories [document = false]
        "Spec"
        "Lexer"
        "LexerExt"
        "Simplifying"
        (*"Sulzmann"*) 
        "Positions"
        "Exercises"

session Paper in "Paper" = Lex +
  options [document = pdf, document_output = "..", document_variants="paper"]
  theories 
    "~~/src/HOL/Library/LaTeXsugar"
    "Paper"
  document_files
    "root.bib"
    "root.tex" 


session Journal in "Journal" = Lex +
  options [document = pdf, document_output = "..", document_variants="journal"]
  theories 
    "~~/src/HOL/Library/LaTeXsugar"
    "Paper"
  document_files
    "root.bib"
    "root.tex"