The principle of dimensional reduction.

Stryzhak, Tamara G.: - Dr. Tamara G. Stryzhak is Professor of Mathematics at the Department of Higher Mathematics of the National Technical University of Ukraine "Kiev Polytechnical Institute," and the Secretary of the Ukrainian National Committee of IAESTE. She studied at the National Taras Shevchenko University of Kiev, and defended her Candidate of Science thesis at the Institute of Mathematics of the USSR Academy of Sciences as well as her Doctor of Science dissertation at the Novosibirsk Section of the USSR Academy of Sciences. She is the author of five monographs, three textbooks, and more than 200 publications in mathematical journals.