Doseva, Nadezhda Ognjanova, and Daniela Chakyrova. “Life Cycle Costs Optimization of Residential Buildings: Part I: A Case Study of External Walls”. ANNUAL JOURNAL OF TECHNICAL UNIVERSITY OF VARNA, BULGARIA 2, no. 2 (December 20, 2018): 62–69. Accessed October 2, 2025. https://aj.tu-varna.bg/index.php/ajtuv/article/view/94.