Let x0 of type ι be given.
Let x1 of type (ι → ο) → ο be given.
Let x2 of type ι → ι → ο be given.
Let x3 of type ι → ο be given.
Apply unknownprop_9c5d94ec6f4b2894fa47ae9dda778f394df5a778dba59355f38751811fc2580d with
30bff.. x0 x1 x2 x3,
x0,
x1,
x2,
x3.
Let x4 of type ι → ι → ο be given.
The subproof is completed by applying H0.