Shlyk, N.I. 2021. “STANDRDS FOR VARIATION RANGE OF RR-INTERVALS AT REST AND IN ORTHOSTASIS IN TRAINING OF RACING SKIERS WITH DIFFERENT TYPES OF REGULATION”. Theory and Practice of Physical Culture, no. 12 (December):27-29. http://tpf1610220.nichost.ru/index.php/TPPC/article/view/76.