@article{CM_1990__75_1_1_0,
     author = {Prasad, Dipendra},
     title = {Trilinear forms for representations of $\mathrm {GL}(2)$ and local $\epsilon $-factors},
     journal = {Compositio Mathematica},
     pages = {1--46},
     publisher = {Kluwer Academic Publishers},
     volume = {75},
     number = {1},
     year = {1990},
     zbl = {0731.22013},
     language = {en},
     url = {http://www.numdam.org/item/CM_1990__75_1_1_0/}
}