[MSDN Library June 1998] BM_GETIMAGE (54.9003189792663%)

MSDN Library Visual Studio 6.0 > Platform SDK > User Interface Services > Controls > Buttons > Button Reference > Button Messages

[MSDN Library April 2000] BM_GETIMAGE (54.9003189792663%)

MSDN Library - April 2000 > Platform SDK > User Interface Services > Windows User Interface > Controls > Buttons > Button Reference > Button Messages