APRILLIANO , Francisko; TUGUR REDATIONO, Nereus; CRISTANTO PUTRA MBULU, Bernardus. COMPARISON OF VARIATIONS OF ROBUSTA AND ARABIKA COFFEE GROUNDS BY COMPOSITION (60%: 40%, 50%: 50%, 40%: 60%) TO DETERMINE THE HARDNESS AND CALORIFIC VALUE OF BRICKETS. Mechanical, Energy and Material (METAL), [S. l.], v. 3, n. 1, p. 01–07, 2025. Disponível em: https://ejournal.widyakarya.ac.id/index.php/metal/article/view/121. Acesso em: 2 jul. 2025.