BTW this paper produced by David Martinez Delgado makes very interesting reading.
https://arxiv.org/pdf/1804.03330.pdf...s772RJsjL5OpF8
Is the author of the paper that our own Mike Sidonio is included in in the discovery of NGC 253-dw2 a dwarf companion of NGC 253.
Paper here.
https://arxiv.org/pdf/1512.03815v2.pdf
Cheers
