Compositio Mathematica, Volume 58 (1986) no. 1, p. 133-134
@article{CM_1986__58_1_133_0,
author = {Frey, Gerhard},
title = {A remark about isogenies of elliptic curves over quadratic fields},
journal = {Compositio Mathematica},
publisher = {Martinus Nijhoff Publishers},
volume = {58},
number = {1},
year = {1986},
pages = {133-134},
zbl = {0596.14021},
mrnumber = {834050},
language = {en},
url = {http://www.numdam.org/item/CM_1986__58_1_133_0}
}

Frey, Gerhard. A remark about isogenies of elliptic curves over quadratic fields. Compositio Mathematica, Volume 58 (1986) no. 1, pp. 133-134. http://www.numdam.org/item/CM_1986__58_1_133_0/

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