Vilutiene, Tatjana, and Pranas Malinauskas. “The Analysis of the Influence of External Environment Factors on the Efficiency of Maintenance Contractors Activities”. Technological and Economic Development of Economy 11, no. 1 (March 31, 2005): 50-58. Accessed December 21, 2024. https://journals.vilniustech.lt/index.php/TEDE/article/view/8494.