Tjalling Charles Koopmans (August 28, 1910 – February 26, 1985) was a Dutch American mathematician and economist.
 He was the joint winner with Leonid Kantorovich of the 1975 Nobel Memorial Prize in Economic Sciences for his work on the theory of the optimum allocation of resources.
 Koopmans showed that on the basis of certain efficiency criteria, it is possible to make important deductions concerning optimum price systems.
The Kantorovich theorem is a mathematical statement on the convergence of Newton's method.
 It was first stated by Leonid Kantorovich in 1940.
Abdullah Sadiq, PhD, "SI" (born 1940), is a Pakistani physicist and ICTP laureate who received the ICTP Prize in the honour of Nikolay Bogolyubov, in the fields of Mathematics and Solid State Physics in 1987 for his contributions to scientific knowledge in the field of Mathematics and Statistical physics.
 He is the professor of physics and current Dean of the Department of Physics of the Air University of the Pakistan Air Force (PAF).
List of all published works of Nikolay Bogolyubov in chronological order (in preparation):
Bogoliubov causality condition is a causality condition for scattering matrix ("S"-matrix) in axiomatic quantum field theory.
 The condition was introduced in axiomatic quantum field theory by Nikolay Bogolyubov in 1955.
In theoretical physics, the Bogoliubov transformation, also known as Bogoliubov-Valatin transformation, were independently developed in 1958 by Nikolay Bogolyubov and John George Valatin for finding solutions of BCS theory in a homogeneous system.
 The Bogoliubov transformation is an isomorphism of either the canonical commutation relation algebra or canonical anticommutation relation algebra.
 This induces an autoequivalence on the respective representations.
 The Bogoliubov transformation is often used to diagonalize Hamiltonians, which yields the stationary solutions of the corresponding Schrödinger equation.
 The Bogoliubov transformation is also important for understanding the Unruh effect, Hawking radiation, pairing effects in nuclear physics, and many other topics.
Unconventional superconductors are materials that display superconductivity which does not conform to either the conventional BCS theory or Nikolay Bogolyubov's theory or its extensions.
Nikolay Nikolayevich Bogolyubov (Russian: Никола́й Никола́евич Боголю́бов ; 21 August 1909 – 13 February 1992), also transliterated as Bogoliubov and Bogolubov, was a Soviet mathematician and theoretical physicist known for a significant contribution to quantum field theory, classical and quantum statistical mechanics, and the theory of dynamical systems; He was the recipient of the 1992 Dirac Prize.
Leonid Vitaliyevich Kantorovich (Russian: Леони́д Вита́льевич Канторо́вич ; ] ) (19 January 19127 April 1986) was a Soviet mathematician and economist, known for his theory and development of techniques for the optimal allocation of resources.
 He is regarded as the founder of linear programming.
 He was the winner of the Stalin Prize in 1949 and the Nobel Memorial Prize in Economics in 1975.
In mathematics, the Krylov–Bogolyubov theorem (also known as the existence of invariant measures theorem) may refer to either of the two related fundamental theorems within the theory of dynamical systems.
 The theorems guarantee the existence of invariant measures for certain "nice" maps defined on "nice" spaces and were named after Russian-Ukrainian mathematicians and theoretical physicists Nikolay Krylov and Nikolay Bogolyubov who proved the theorems.

Question: Which Russian mathematician was born the earliest, Nikolay Bogolyubov or Leonid Kantorovich
Answer: Nikolay Nikolayevich Bogolyubov