SIRGHI, Nicoleta, Mihaela NEAMTU, Gabriela MIRCEA, and Doriana RAMESCU. 2019. “The Deterministic Model With Time Delay for a New Product Diffusion in a Market”. Timisoara Journal of Economics and Business 11 (1), 55-66. http://tjeb.ro/index.php/tjeb/article/view/TJEB-vol11-2018-iss1-art4-SIRGHI.