Kramens, Janis, et al. “RESEARCH OF BIOMASS MICRO-COGENERATION SYSTEM INTEGRATION WITH A SOLAR PV PANELS IN ZERO-ENERGY FAMILY BUILDING”. ENVIRONMENT. TECHNOLOGY. RESOURCES. Proceedings of the International Scientific and Practical Conference, vol. 1, June 2021, pp. 132-8, https://doi.org/10.17770/etr2021vol1.6568.