This seems both interesting and hard to pinpoint. Köck (1991; 1998, 4.6b) credits Fulton-Lang (1985) and Soulé (1985, cf. Thm 7), but your suggestion that the theorem must have been “known” earlier is also well-supported. For one thing, Rössler (1999, §1) finds it in Manin (1969, Thm 16.6). For another, Dyer (1962) (cited by Eckmann at ICM (1963), Adams (1965, (iii) p. 152), Fuks (1973, pp. 349–350), and reprinted in Adams (1972)) starts:

This lecture is principally an exposition of a folk theorem of a Riemann-Roch type for general cohomology theories known to Adams, Atiyah, Hirzebruch... .

While these authors don’t spell out how this “folk” theorem includes yours, Panin (2004, §0.1; 2004, p. 823) says at least that his Theorem 2.5.3 “inspired by a Riemann-Roch theorem from [Dy]”, does. See also Smirnov (2006, 2.5.3).

So my impression is that specialists understood the Adams Riemann-Roch theorem as an instance of the more general Dyer-Riemann-Roch theorem, long before any of them bothered to name it.

This seems both interesting and hard to pinpoint. Köck (1991; 1998, 4.6b) credits Fulton-Lang (1985) and Soulé (1985, cf. Thm 7), but your suggestion that the theorem must have been “known” earlier is also well-supported. For one thing, Rössler (1999, §1) finds it in Manin (1969, Thm 16.6). For another, Dyer (1962) (cited by Eckmann at ICM (1963), Adams (1965, (iii) p. 152), Fuchs (1973, pp. 349–350), and reprinted in Adams (1972)) starts:

This lecture is principally an exposition of a folk theorem of a Riemann-Roch type for general cohomology theories known to Adams, Atiyah, Hirzebruch... .

While these authors don’t spell out how this “folk” theorem includes yours, Panin (2004, §0.1; 2004, p. 823) says at least that his Theorem 2.5.3 “inspired by a Riemann-Roch theorem from [Dy]”, does. See also Smirnov (2006, 2.5.3).

So my impression is that specialists understood the Adams Riemann-Roch theorem as an instance of the more general Dyer-Riemann-Roch theorem, long before any of them bothered to name it.

This seems both interesting and hard to pinpoint. Köck (1991; 1998, 4.6b) cites both Soulé (1985, cf. Thm 7) and Fulton-Lang (1985), but your suggestion that the theorem must have been “known” earlier is also well-supported. For one thing, Rössler (1999, §1) finds it in Manin (1969, Thm 16.6). For another, Dyer (1962) (cited by Eckmann at ICM (1963) and reprinted in Adams (1972)) starts:

This lecture is principally an exposition of a folk theorem of a Riemann-Roch type for general cohomology theories known to Adams, Atiyah, Hirzebruch... .

While these authors don’t spell out how this “folk” theorem includes yours, Panin (2004, §0.1; 2004, p. 823) says at least that his Theorem 2.5.3 “inspired by a Riemann-Roch theorem from [Dy]”, does.

This seems both interesting and hard to pinpoint. Köck (1991; 1998, 4.6b) credits Fulton-Lang (1985) and Soulé (1985, cf. Thm 7), but your suggestion that the theorem must have been “known” earlier is also well-supported. For one thing, Rössler (1999, §1) finds it in Manin (1969, Thm 16.6). For another, Dyer (1962) (cited by Eckmann at ICM (1963), Adams (1965, (iii) p. 152), Fuks (1973, pp. 349–350), and reprinted in Adams (1972)) starts:

This lecture is principally an exposition of a folk theorem of a Riemann-Roch type for general cohomology theories known to Adams, Atiyah, Hirzebruch... .

While these authors don’t spell out how this “folk” theorem includes yours, Panin (2004, §0.1; 2004, p. 823) says at least that his Theorem 2.5.3 “inspired by a Riemann-Roch theorem from [Dy]”, does. See also Smirnov (2006, 2.5.3).

So my impression is that specialists understood the Adams Riemann-Roch theorem as an instance of the more general Dyer-Riemann-Roch theorem, long before any of them bothered to name it.