Voiku, Ivan. “THE DEVICE OF THE SHALLOW FRAME (HALF-FRAME) WITH QUICK FITTING OF A BEESWAX FOUNDATION AND ITS ADVANTAGE”. ENVIRONMENT. TECHNOLOGIES. RESOURCES. Proceedings of the International Scientific and Practical Conference 1 (June 20, 2019): 336–338. Accessed May 5, 2024. https://journals.ru.lv/index.php/ETR/article/view/4104.