Media type: Electronic Conference Proceeding Title: Ceilometer observation of Saharan dust over mountain valley of Sofia, Bulgaria Contributor: Kolev, Nikolay; Evgenieva, Tsvetina; Grigorov, Ivan; Deleva, Atanaska; Ivanov, Danko; Danchovski, Ventsislav; Savov, Plamen; Petkov, Doyno imprint: SPIE, 2015 Published in: 18th International School on Quantum Electronics: Laser Physics and Applications Extent: Language: Not determined DOI: 10.1117/12.2086082 ISSN: 0277-786X Origination: Footnote: