Case Study on Combined Lidar-Photometer Retrieval of Volcanic ASH PropertiesJosef Gasteiger, Matthias Wiegner, Carlos Toledano, Silke Groß and Volker FreudenthalerEPJ Web of Conferences, 119 (2016) 07004DOI: https://doi.org/10.1051/epjconf/201611907004