The design of a collision avoidance system for use by Pilots operating on the airport ramp and in taxiway areas. - Joan Cahill; Peter Redmond; Sofiane Yous; Gerard Lacey; William Butler (Cogn. Technol. Work., 2013)

A Modified McCumber Cube as a Basis for a Taxonomy of Cyber Attacks. - Chuck Easttom; William Butler (CCWC, 2019)

The Iran-Saudi Cyber Conflict. - Chuck Easttom; William Butler (Int. J. Cyber Warf. Terror., 2021)