Serotypes and extended spectrum beta-lactam resistance in aminoglycoside resistant Pseudomonas aeruginosa isolates from two Belgian general hospitals: a seven year study36650, Vanhoof, R., Godard C., Nulens E., Nyssen H.J., Wildemauwe C., Hubrechts J.M., Maes P., and Hannecart-Pokorni E. , J.Hosp.Infect., 0/6/1993, Volume 24, Issue 2, Number 138, p.129 - 138, (1993)