Zhelyazkova, I.,
Mihaylov, A., &
Ivanov, M.
().
A WINDOWS-based tool for portfolio analysis of the company product-market strategy. // <I>Proceedings<D> of the Fist International conference “Actual tasks and multidisciplinary sciences”, Lozenetz, 6-8 june, 2007. - Vol. 4. - Rousse : Univ. of Rousse, 2007, p. 245-250..