A Free Boundary Problem: The Flow of Two Immiscible Fluids in a One-Dimensional Porous Medium, I
L. Evans
Indiana University Mathematics Journal
1977
text
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10.1512/iumj.1977.26.26074
10.1512/iumj.1977.26.26074
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Indiana Univ. Math. J. 26 (1977) 915 - 932
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