Number of fermion generations from a novel grand unified model Pritibhajan Byakti, David Emmanuel-Costa, Arindam Mazumdar and Palash B. Pal Eur. Phys. J. C, 74 2 (2014) 2730 Published online: 31 January 2014 DOI: 10.1140/epjc/s10052-014-2730-9