Hey Hans et al., Using ConTeXt ver: 2012.01.23 19:45 MKIV fmt: 2012.1.24 int: english/english and LuaTeX, Version beta-0.71.0-2012012215 (rev 4358), I get the following error while typesetting my book: ! Undefined control sequence. <argument> \doconvertedstructurecounter [\v!formula ][] \flushbothlabelclass #1#2#3->#1#3 #2 <argument> ...spaces \doplacecurrentformulanumber \removeunwantedspaces \dos... \flushbothlabelclass #1#2#3->#1#3 #2 \namedtaggedlabeltexts ...\dostarttagged {#1}{#2}} \dostoptagged \endgroup \placecurrentformulanumber ...moveunwantedspaces } \formulaparameter \c! right... ... l.120 \stopformula ? E You want to edit file Source/Terms_and_Concepts/Terms_and_Concepts.tex at line 120 The line it is referring to is the last line of the following code snippet: ... \placeformula[formula:Verhulst equation] \startformula \math{P(t) = \frac{K P_0 {\it e}^{rt}} {K + P_0({\it e}^{r t} - 1)}} \stopformula % Line 120 ... -- Kip Warner -- Software Engineer OpenPGP encrypted/signed mail preferred http://www.thevertigo.com