y - JOUR AU - Abujabal, Hamza A. S. PY - 1990 DA - 1900/01/01 TI -左的交换性定理 年代 -unit rings SP - 392717 VL - 13 AB - SN - 0161-1712 UR - https://doi.org/10.1155/S0161171290001065 DO - 10.1155/S0161171290001065 JF - International Journal of Mathematics and Mathematical Sciences PB - Hindawi Publishing Corporation KW - ER -