The recommended Hotel for the international participants is the following:
City Express Plus Patio Universidad
Avenida Popocatépetl No. 546, Col. Xoco Del. Benito Juárez C.P.
Mexico City, DF, 03330, México
Tel. 001 (877) 860 2742

For booking please use the following link:

It is located in the southwest part of Mexico City, in the middle of two shopping malls with a lot of restaurants, relative close to UNAM Metro station and a walking distance away from two Metro stations (Coyoacan and Zapata) on the same line as the Metro Ciudad Universitaria, where the ICN (Nuclear Sciences Institute) is located.
Directions for public transportations are available here.