APA (7th ed.) Citation

Gomes, M. C., Cavique, L., & Themido, I. (2011). The crew timetabling problem: An extension of the crew scheduling problem.

Chicago Style (17th ed.) Citation

Gomes, Marta Castilho, Luís Cavique, and Isabel Themido. The Crew Timetabling Problem: An Extension of the Crew Scheduling Problem. 2011.

MLA (8th ed.) Citation

Gomes, Marta Castilho, et al. The Crew Timetabling Problem: An Extension of the Crew Scheduling Problem. 2011.