ANDRÉ FILIPE TEIXEIRA E SEABRA, JOSÉ ANTONIO RIBEIRO R. Maia, DENISA M. MENDONÇA, MARTINE THOMIS, CARL J. CASPERSEN, JANET E. FULTON,
Age and Sex Differences in Physical Activity of Portuguese Adolescents Medicine and Science in Sports and Exercise. ,vol. 40, pp. 65- 70 ,(2008) ,
10.1249/MSS.0B013E3181593E18