Twitter responded in awesome fashion. And even better, Jackie Monkowiez put it all in a Storify:
Best Twitter Thread Ever!
These are some of the suggested papers:
The Great Big Review Paper
Renzini+ 2006
http://www.annualreviews.org/doi/abs/10.1146/annurev.astro.44.051905.092450
Graham+ 2013
http://adsabs.harvard.edu/abs/2013pss6.book...91G
Ongoing discussion on the Initial Mass Function in these following papers:
Cappellari+ 2016
https://arxiv.org/abs/1602.04267
Lyubenova+ 2016
https://arxiv.org/abs/1606.07448
Smith+ 2014
http://adsabs.harvard.edu/abs/2014MNRAS.443L..69S
Conroy & van Dokkum+ 2012
http://adsabs.harvard.edu/abs/2012ApJ...760...70V
https://ui.adsabs.harvard.edu/#abs/2012ApJ...760...71C/abstract
and also there were these papers:
Schombert+ 2009/2015
http://adsabs.harvard.edu/abs/2015AJ....150..162S
http://adsabs.harvard.edu/abs/2009ApJ...699.1530S
Bender+ 1993a,b
http://adsabs.harvard.edu/abs/1992ApJ...399..462B
http://adsabs.harvard.edu/abs/1993ApJ...411..153B