THE DEMING CYCLE (PDCA) CONCEPT AS AN EFFICIENT TOOL FOR CONTINUOUS QUALITY IMPROVEMENT IN THE AGRIBUSINESS Статья Dudin M.N., Frolova E.E., Gryzunova N.V., Shuvalova E.B. Asian Social Science. Canadian Center of Science and Education. Том Vol 11 No 1. 2015. С. 239-246