TY - JOUR AU - G. Czichowski TI - Geometrical Aspects of SL(2)-Invariant Second Order Ordinary Differential Equations JO - Journal of Lie Theory PY - 1993 SP - 231 EP - 238 VL - 3 IS - 2 UR - https://jolt.centre-mersenne.org/articles/10.5802/jolt.68/ DO - 10.5802/jolt.68 ID - JOLT_1993_3_2_a6 ER -