Sorting these covers by decade
The Outsiders by decade
S. E. Hinton and 2 others
32 covers from 32 printings with a known year, 2010s back to 1960s
2010s
4 covers · 4 publishers, Livebook and Wu zhou chuan bo chu ban she among them · 2 languages
2000s
12 covers · 7 of 13 printings say paperback · 10 publishers, Speak and Viking Juvenile among them · 2 languages
1990s
5 covers · 2 of 5 printings say paperback · 5 publishers, Deutscher Taschenbuch Verlag and Heinemann Educational Publishers among them · 2 languages
1980s
2 covers · 3 of 5 printings say paperback · 4 publishers, Alfaguara and Bt Bound among them · 2 languages
1970s
3 covers · 3 publishers, Laurel-Leaf Library and Gollancz among them
1960s
6 covers · 3 of 7 printings say paperback · 5 publishers, Viking Press, Dell Publishing and Dell among them
Covers from Open Library, each in the decade of the earliest printing that carries it. What the catalogues never scanned is missing here too. See the whole wall.