Черный, Р., and О. Кинаш. “THE BANRKUPCY PROBABILITY AND AN OPTIMAL INSURANCE RATE IN CASE OF PAYMENTS WITH LOGNORMAL DISTRIBUTION”. Modern Engineering and Innovative Technologies, vol. 3, no. 06-03, Dec. 2017, pp. 99-104, doi:10.30890/2567-5273.2018-06-03-055.