39 ABNT NBR 8451-1-2020 2020-03-31 Portuguese Reinforced and prestressed concrete pole for electric power distribution and transmission lines Part 1: Requirements 40 ABNT NBR 10151 Errata 1-2020 2020-03-31 Portuguese Ac煤stica - Medi莽茫o e avalia莽茫o de n铆veis de press茫o sonora em ...