Star Trek The Animated Series. Premiered in 1973 and ran until 1975. It featured all the original actors' voices.
Creating the Filmation Generation – Andy Mangels (Co-Author) Interview | TrekCore Blog
Star Trek Animated Series Plus Other Animation
Star Trek TAS Crew
Animated Star Trek
Star Trek: The Animated Series
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Saturday Morning Cartoons
Star Trek - animated series
Star Trek The Animated Series (1973 - 1974).
Juan Ortiz Animated Series Poster
Star Trek Más
Star Trek (TAS)... an underappreciated series. The episode "Beyond the Farthest Star" creeped me right out when I was a kid.