Study of qualitative composition and quality indicators of black thorn (Prúnus spinósa L.) leavesА.А. Nazarychev, N.V. Nesterova, I.V. Sanin, G.V. Nesterov and S. KondrashevE3S Web of Conf., 462 (2023) 02029DOI: https://doi.org/10.1051/e3sconf/202346202029