@article{KramerLaeuterRubinetal.2017, author = {Tobias Kramer and Matthias L{\"a}uter and Martin Rubin and Kathrin Altwegg}, title = {Seasonal changes of the volatile density in the coma and on the surface of comet 67P/Churyumov-Gerasimenko}, journal = {Monthly Notices of the Royal Astronomical Society}, volume = {469}, pages = {S20 -- S28}, doi = {10.1093/mnras/stx866}, year = {2017}, }