@article{articlee2033a61,
title   = {Subspace identification methods applied to activated sludge processes: a performance comparison study},
author = {Zanabria Sotomayor, Oscar Alberto and Park, Song Won and Garcia, Claudio},
year = {2001},
journal   = {Boletim Técnico da Escola Politécnica da USP. Departamento de Engenharia de Telecomunicações e Controle}
}