@article{7357, author = "Grossi, Mario D. and Gay, Ray H.", title = "Doppler Measurements of the Ionosphere on the Occasion of the Apollo-Soyuz Test Project. Part I: Computer Simulation of Ionospheric - Induced Doppler Shifts ", year = "1975", note = "2x1 sv., příl. The Model of the Summer 1975 Ionosphere", }