Useful Links

Giant air shower arrays
Pierre Auger Observatory   https://www.auger.org/
Telescope Array               http://www.telescopearray.org

Cosmic ray groups:
In P.N. Lebedev Physical Institute of RAN  http://www.lebedev.ru/
In Skobeltsyn Institute of Nuclear Physics of MSU  http://www.sinp.msu.ru/
In Institute for Nuclear Research of RAN http://www.inr.ru/english.html
In Altai State University    http://www.asu.ru/