0377-94240377-9424S0377-9424201600010008110.15517/rac.v40i1.25336USAUnited StateColombia00062016000620164018188200861394-4042004852008336200173251-62200659189-96200760350-8197030203-62006200993586-60320093-4199660659-68201430389NATIONAL RESEARCH COUNCIL19967th ed2422013122200729217-22200080405-13200558256-66