I have four forms: 

Form B has a lookup field based on Form A;

Form C has a lookup field based on Form B;

Form D has a lookup field based on Form C. 

Now when I develop a view based on Form D, 

I can display fields from forms C and B, but not A.

There is no way I can link the forms to display any field Form A, though Form A

is used in Form B, and B in C, and C in D.