Trends in the development of proficiency testing for chemical analysis:: focus on food and environmental matrices - Olivares, Igor Renato Bertoni; Souza, Gilberto Batista de; Nogueira, Ana Rita de Araujo; Pacces, Vitor Hugo Polisel; Grizotto, Pamela Aparecida; Lima, Paula Souza da Silva Gomes; Bontempi, Rhaissa Mecca (Accreditation and Quality Assurance, 2022)