Leonid Kulikov was born on the 2nd of November 1914 in the Donetsk region. After graduating from the vocational school, he worked for some time as a librarian in the town of Slavyansk. In 1934 L. Kulikov was admitted to the Moscow State Pedagogical Institute (currently the Moscow State Pedagogical University, MSPU), majoring in physics and mathematics. His brilliant mathematical talent was highly appreciated by many leading scientists teaching there. Upon graduation from the Institute in 1938, he commenced his graduate studies at the Department of Algebra. In May 1941, Leonid Kulikov successfully defended his Ph.D. thesis titled "On the Theory of Abelian Groups of Arbitrary Cardinality". This work immediately received high evaluations from the mathematical community and made the author well known worldwide.
In 1951, L. Kulikov defended his Doctor of Science thesis titled "Generalized Primary Groups" at the Department of Mathematics and Mechanics of Leningrad State University. Mathematical work of Leonid Yakovlevich are extremely deep, they currently are classic and come in gold fund of algebraic science. Ideas and methods developed by Kulikov are the basis of the modern theory of Abelian groups.
In fact, Abelian group theory became a separate branch of modern algebra thanks to Kulikov’s works. In 1954 the famous Hungarian mathematician Dr. Tiboi Szele wrote: “Today it is quite obvious that the
most important contribution to the theory of infinite Abelian groups was made by Dr. L. Y. Kulikov, and
Dr. Kulikov is the world’s leading scientist in this field.”
Characterizing the scientific contribution of Leonid Kulikov, the outstanding Soviet algebraist and academician A. I. Maltsev wrote in 1964: “Dr. L. Y. Kulikov is one of the most brilliant algebraists today, one of the founders of modern commutative group theory. His contribution to this area cannot be overestimated. This can be easily ascertained just by looking at the chapters on commutative group theory in the monograph Groups Theory by A. G. Kurosh or Abelian Groups by L. Fuchs. The name of Kulikov can be seen in almost every paragraph. Most fundamental theorems or their modern formulations belong to Kulikov.”
A detailed biography can be found from the following link Biography