Zhelyazkova, G., Zhelyazkova, S. Towards Viability and Sustainability of the Tourism in Bulgaria. Batumi: Batumi State Maritime Academy, 2016 pp. 175 - 185, ISBN 978-9941-0-9114-8.
Zhelyazkova, G., Zhelyazkova, S. Towards Viability and Sustainability of the Tourism in Bulgaria. Batumi: Batumi State Maritime Academy, 2016 pp. 175 - 185, ISBN 978-9941-0-9114-8.
Zhelyazkova, G., Zhelyazkova, S. (2016) Towards Viability and Sustainability of the Tourism in Bulgaria, Batumi: Batumi State Maritime Academy pp. 175 - 185, ISBN 978-9941-0-9114-8.
Zhelyazkova, G., & Zhelyazkova, S. (2016). Towards Viability and Sustainability of the Tourism in Bulgaria. Batumi: Batumi State Maritime Academy, pp. 175 - 185.
Zhelyazkova G, Zhelyazkova S. Towards Viability and Sustainability of the Tourism in Bulgaria. Batumi: Batumi State Maritime Academy; 2016. p. pp. 175 - 185. ISBN: ISBN 978-9941-0-9114-8.
