Krajewski, Łukasz, M. Witkowska-Dąbrowska, and I. M. . de Jesus. “Influence of a Financial Crisis and the Covid-19 Pandemic on Prices of Cereals in Poland”. Olsztyn Economic Journal, vol. 17, no. 1, Sept. 2022, pp. 71-82, doi:10.31648/oej.8654.