For mastering advanced integral calculation, consider these books: "Interesting Integrals" by Nahin, "Irresistible Integrals" by Boros and Moll, and "Solved Problems for the Gamma and Beta Functions, Legendre Polynomials, and Bessel functions" by Farrel and Ross. Also, "Almost Impossible Integrals, Sums, and Series" by Cornel Ioan Vălean. For practical skills, learn a computer algebra system (CAS) like Maxima or Sage. For specific advanced concepts, explore high-voted Q&A on Math StackExchange or Mathoverflow.