Subgroups between special linear groups over a ring and its subring

All the subgroups between the special linear groups SL(n, o) and SL(n, o) are described in the following two cases: 1) o is a real-closed field, and o is its algebraic closure; 2) o is a Euclidean ring, and o is its quotient field.Translated from Matematicheskie Zametki, Vol. 6, No. 3, pp. 335–345, September, 1969.