APA (7th ed.) Citation

PC Software Interest Group (Sunnyvale, Calif.). (1991). The PC-SIG encyclopedia of shareware (4th ed.). Windcrest.

Chicago Style (17th ed.) Citation

PC Software Interest Group (Sunnyvale, Calif.). The PC-SIG Encyclopedia of Shareware. 4th ed. Blue Ridge Summit, PA: Windcrest, 1991.

MLA (9th ed.) Citation

PC Software Interest Group (Sunnyvale, Calif.). The PC-SIG Encyclopedia of Shareware. 4th ed. Windcrest, 1991.

Warning: These citations may not always be 100% accurate.