Daniel A. Menascé Virgilio Almeida Rudolf H. Riedi Flávia Ribeiro Rodrigo C. Fonseca Wagner Meira Jr. In search of invariants for e-business workloads. 56-65 2000 ACM Conference on Electronic Commerce http://doi.acm.org/10.1145/352871.352878 db/conf/sigecom/sigecom2000.html#MenasceARRFM00