APA (7th ed.) Citation

Loia, V., & Quaggetto, M. (1996). The Opla System: Designing Complex Systems in an Object-oriented Logic Programming Framework. Computer Journal, 39(1), 20. https://doi.org/10.1093/comjnl/39.1.20

Chicago Style (17th ed.) Citation

Loia, V., and M. Quaggetto. "The Opla System: Designing Complex Systems in an Object-oriented Logic Programming Framework." Computer Journal 39, no. 1 (1996): 20. https://doi.org/10.1093/comjnl/39.1.20.

MLA (9th ed.) Citation

Loia, V., and M. Quaggetto. "The Opla System: Designing Complex Systems in an Object-oriented Logic Programming Framework." Computer Journal, vol. 39, no. 1, 1996, p. 20, https://doi.org/10.1093/comjnl/39.1.20.