[Probabilistic Counting Algorithms for Data Base Applications](https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&doi=b36c153be410c0d937d7583de557c0375506d15a) by Philppe Flajolet, Nigel Martin
[The Space Complexity of Approximating the Frequency Moments](http://www.cs.ucsb.edu/~veronika/MAE/spacecomplexityapproxfreqmoments_alon_99.pdf) by Noga Alon, Yossi Matias, Mario Szegedy