Measurement Uncertainty and Risk of False Compliance Assessment Applied to Carbon Isotopic Analyses in Natural Gas Exploratory Evaluation oleh Fabiano Galdino Leal, Alexandre de Andrade Ferreira, Gabriel Moraes Silva, Tulio Alves Freire, Marcelo Ribeiro Costa, Erica Tavares de Morais, Jarbas Vicente Poley Guzzo, Elcio Cruz de Oliveira