[MSDN Library April 2000] Optional Methods in Control Interfaces (80%)

MSDN Library - April 2000 > Platform SDK > Component Services > COM > Controls and Property Pages > Guide > ActiveX Control and Control Container Guidelines > Controls

[MSDN Library April 2000] Optional Methods (53.0263157894737%)

MSDN Library - April 2000 > Platform SDK > Component Services > COM > Controls and Property Pages > Guide > ActiveX Control and Control Container Guidelines > Containers

[MSDN Library April 2000] Optional Message (44.0021929824561%)

MSDN Library - April 2000 > Windows Resource Kits > Windows 2000 Server Resource Kit > TCP/IP Core Networking Guide > Appendixes > DHCP Options > DHCP Extensions

[MSDN Library April 2000] Optional Navigation Controls (32.4013157894737%)

MSDN Library - April 2000 > Windows CE Documentation > Application Development > Palm-size PC > Palm-size PC Controls > Navigation Controls

[MSDN Library April 2000] Optional Messages for Waveform Input Drivers (25.3068181818182%)

MSDN Library - April 2000 > DDK Documentation > Windows 95 DDK > Windows 95 Documentation > Design Guide > Multimedia Device Drivers > Audio Device Drivers > Waveform Input Driver Messages