Holographic dark energy: constraints on the interaction from diverse observational data sets Purba Mukherjee, Ankan Mukherjee, H. K. Jassal, Ananda Dasgupta and Narayan Banerjee Eur. Phys. J. Plus, 134 4 (2019) 147 Published online: 12 April 2019 DOI: 10.1140/epjp/i2019-12504-7