TY - JOUR AU - Block, Richard E. TI - On the Extensions of Lie Algebras JO - Canadian journal of mathematics PY - 1968 SP - 1439 EP - 1450 VL - 20 IS - 1 UR - http://geodesic.mathdoc.fr/articles/10.4153/CJM-1968-145-5/ DO - 10.4153/CJM-1968-145-5 ID - 10_4153_CJM_1968_145_5 ER -