SGEM 2015. 15th International Multidisciplinary Scientific GeoConference. Water Resources. Forest, Marine and Ocean Ecosystems : conference proceedings. Albena, Bulgaria, 18. - 24. 6. 2015. Volume I Hydrology & Water Resources. 1. vyd. Sofia : STEF 92 Technology, 2015. 794 s. ISBN 978-619-7105-36-0. ISSN 1314-2704.