[MSDN Library June 1998] isdigit (100%)
MSDN Library Visual Studio 6.0 > Visual C++ Documentation > Reference > C/C++ Language and C++ Libraries > Standard C++ Library Reference > locale
[MSDN Library June 1998] isdigit, iswdigit (25.6397615864528%)
MSDN Library Visual Studio 6.0 > Visual C++ Documentation > Using Visual C++ > Visual C++ Programmer's Guide > Run-Time Library Reference > Alphabetic Function Reference > I Through K
[MSDN Library June 1998] ISDIGIT( ) Function (14.9407894736842%)
MSDN Library Visual Studio 6.0 > Visual FoxPro Documentation > Reference > A to Z Language Reference