April 6, 1977: Angels debut their first free-agent class; Mariners
History of the Seattle Mariners - Wikipedia
1977 Seattle Mariners Inaugural Series Program
1977 Seattle Mariners Inaugural Series Program
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Unocal 76 Pin #1 Opening Night 6 April 1977 Seattle Mariners v California Angels
1977 Baseball Cards Update: 1977 California Angels
Seattle Mariners' first season (1977)
California Angels
Mariners GameDay — August 9 vs. New York-AL, by Mariners PR
VEB Historical Hall of Fame Ballot: Part Nine - Viva El Birdos
Seattle Mariners' first season (1977)
Seattle Mariners, History & Notable Players
Official Seattle Mariners Website