All four issues of the a+t magazine Density series are the start of a+t research group's investigation on housing. Density II, which printed version is sold out, is now available in digital version at Zinio and by projects in PDF format.

The series analyses the projects because of their contribution to the dense city. The research made through the magazine has been further developed in the books: Density, Dbook, Density projects, HoCo, Next and Density is Home; which became a reference for publications about collective housing worldwide.