Let x0 of type ι be given.
Let x1 of type ι → ο be given.
Let x2 of type ι → ο be given.
Let x3 of type ι be given.
Apply unknownprop_d6268ec7e4825027a1689766f799a931a33ec03a29326c7ca0edf73f7b2d8eaa with
9a89f.. x0 x1 x2 x3,
x0,
x1,
x2,
x3.
Let x4 of type ι → ι → ο be given.
The subproof is completed by applying H0.