Neuro-swarm intelligent computing to solve the second-order singular functional differential model Zulqurnain Sabir, Muhammad Asif Zahoor Raja, Muhammad Umar and Muhammad Shoaib Eur. Phys. J. Plus, 135 6 (2020) 474 Published online: 05 June 2020 DOI: 10.1140/epjp/s13360-020-00440-6