  We obtain necessary optimality conditions for variational problems with a
Lagrangian depending on a Caputo fractional derivative, a fractional and an
indefinite integral. Main results give fractional Euler-Lagrange type equations
and natural boundary conditions, which provide a generalization of previous
results found in the literature. Isoperimetric problems, problems with
holonomic constraints and depending on higher-order Caputo derivatives, as well
as fractional Lagrange problems, are considered.
