Maftei, M., Shivarov, A. Environmental Aspect of Sustainable Development. Варна: Унив. изд. Наука и икономика, 2007 с. 34 - 39, 978-954-21-0283-0.
Maftei, M., Shivarov, A. Environmental Aspect of Sustainable Development. Варна: Унив. изд. Наука и икономика, 2007 с. 34 - 39, 978-954-21-0283-0.
Maftei, M., Shivarov, A. (2007) Environmental Aspect of Sustainable Development, Варна: Унив. изд. Наука и икономика с. 34 - 39, 978-954-21-0283-0.
Maftei, M., & Shivarov, A. (2007). Environmental Aspect of Sustainable Development. The Case of Galati District. Варна: Унив. изд. Наука и икономика, с. 34 - 39.
Maftei M, Shivarov A. Environmental Aspect of Sustainable Development: The Case of Galati District. Варна: Унив. изд. Наука и икономика; 2007. p. с. 34 - 39. ISBN: 978-954-21-0283-0.
