Bivainis, Juozas, and Irena Daukševičiūtė. “An Optimisation Model for the Marketing Programmes of Companies”. Business: Theory and Practice 14, no. 3 (September 23, 2013): 228-239. Accessed April 27, 2024. https://journals.vilniustech.lt/index.php/BTP/article/view/8458.