WRZESIŃSKI, Z. Substantial Balance Equation of Internal Energy as Viewed by the Balance Theory. Engineering Transactions, [S. l.], v. 50, n. 1-2, p. 91–102, 2015. DOI: 10.24423/engtrans.511.2002. Disponível em: http://et.ippt.gov.pl/index.php/et/article/view/511. Acesso em: 17 jan. 2026.