[NTG-context] Where is ifforwardreference defined?

[Mike Bird]

\somewhere sometimes prints the wrong text.  To track down the
problem I tried to find the definition for \ifforwardreference.
I can see where \iffowardreference is declared to be a \newif but
I can't find where the algorithm is defined:

$ grep -r ifforwardreference .
./tex/context/base/core-ref.tex:\newif\ifforwardreference
./tex/context/base/core-ref.tex:\def\doifforwardreferenceelse#1#2%
./tex/context/base/core-ref.tex:  {\ifforwardreference#1\else#2\fi}
./tex/context/base/core-ref.tex:     {\ifforwardreference
./tex/context/base/core-ref.tex:        \ifforwardreference
Binary file ./web2c/pdfetex/cont-de.fmt matches
Binary file ./web2c/pdfetex/cont-en.fmt matches
Binary file ./web2c/pdfetex/cont-it.fmt matches
$

Does anyone know where \ifforwardreference is defined?

Thanks,

--Mike Bird