@article{IM_1978__50_142614,
     author = {M. Adler},
     title = {On a {Trace} {Functional} for {Formal} {Pseudo-Differential} {Operators} and the {Symplectic} {Structure} of the {Korteweg-Devries} {Type} {Equation.}},
     journal = {Inventiones mathematicae},
     pages = {219--248},
     publisher = {mathdoc},
     volume = {50},
     year = {1978},
     zbl = {0393.35058},
     url = {http://geodesic.mathdoc.fr/item/IM_1978__50_142614/}
}