The essence and basic product selling strategies in recreation and health tourism Oleksandr Hladkyi, Svitlana Sakhno, Olena Khadzhynova, Alla Dakal and Larysa Kapranovа E3S Web Conf., 255 (2021) 01033 Published online: 03 May 2021 DOI: 10.1051/e3sconf/202125501033