DOCS_TARGET_REQUIRE_PROGRAM(INKSCAPE, inkscape, HTMLHELP)
DOCS_TARGET_REQUIRE_PROGRAM(INKSCAPE, inkscape, PEARSON)
DOCS_TARGET_REQUIRE_PROGRAM(INKSCAPE, inkscape, PLUCKER)
-DOCS_TARGET_REQUIRE_PROGRAM(INKSCAPE, inkscape, FOPDF)
DOCS_TARGET_REQUIRE_PROGRAM(EPSTOPDF, epstopdf, PDF)
DOCS_TARGET_REQUIRE_PROGRAM(PNGTOPNM, pngtopnm, PS)
DOCS_TARGET_REQUIRE_PROGRAM(HTML2TEXT, html2text, TXT)
DOCS_TARGET_REQUIRE_PROGRAM(PERL, perl, UNDOCUMENTED)
DOCS_TARGET_REQUIRE_PROGRAM(XMLLINT, xmllint, VALIDATE)
-DOCS_TARGET_REQUIRE_PROGRAM(FOP, fop, FOPDF)
DOCS_TARGET_REQUIRE_PROGRAM(DB2TEXI, docbook2x-texi, TEXI)
DOCS_TARGET_REQUIRE_PROGRAM(MAKEINFO, makeinfo, TEXIINFO)
DOCS_DEFINE_TARGET(PEARSON, ALL, [pearson-compatible XML], [pearson])
DOCS_DEFINE_TARGET(PLUCKER, HTML, [plucker versions], [plucker])
DOCS_DEFINE_TARGET(VALIDATE, ALL, [validating docbook output], [])
-DOCS_DEFINE_TARGET(FOPDF, ALL, [PDF versions thru FO], [fo-pdf])
DOCS_DEFINE_TARGET(TEXI, ALL, [TexInfo versions], [texi])
DOCS_DEFINE_TARGET(TEXIINFO, ALL, [TexInfo Info versions], [texiinfo])
DOCS_DEFINE_TARGET(UNDOCUMENTED, MANPAGES, [list of undocumented options], [undocumented])