In the following example, Mutant Enemy is the primary production company, and “Hush” was released in 1999.
“Hush.” Buffy the Vampire Slayer, created by Joss Whedon, performance by Sarah Michelle Gellar, season 4, Mutant Enemy, 1999.
However, it may be necessary to give fuller or modified date information. If referring to a specific date, for example, use that date instead of just the year. Thus the network and full date is cited NOT the producer.
“Hush.” Buffy the Vampire Slayer, created by Joss Whedon, performance by Sarah Michelle Gellar, season 4, episode 10, WB Television Network, 14 Dec. 1999.
NOTE: These kinds of distinctions can be rather challenging. If unsure, as always, ask your instructor.