Investigation of quantum coherence effects in a multilevel atom induced by three laser fields Saswati Dey, Nilanjan Aich, Chanchal Chaudhuri and Biswajit Ray Eur. Phys. J. D, 69 2 (2015) 43 Published online: 12 February 2015 DOI: 10.1140/epjd/e2014-50525-4