1. Solution of the congruence subgroup problem for 𝑆𝐿_{𝑛}(𝑛≥3) and 𝑆𝑝_{2𝑛}(𝑛≥2);Bass, H.;Inst. Hautes \'{E}tudes Sci. Publ. Math.,1967
2. [B-T] H. Bass and J. Tate, K2 of global fields (in preparation).
3. On the structure of the 𝐺𝐿₂ of a ring;Cohn, P. M.;Inst. Hautes \'{E}tudes Sci. Publ. Math.,1966
4. [D] R. K. Dennis, Surjective stability for the functor K2 (to appear).