E. LITTA; S. NARMADHA. Proper Colourings in r -Regular Inverse Sum Indeg Index Graphs. Research and Applications Towards Mathematics and Computer Science Vol. 9, [S. l.], p. 66–76, 2024. DOI: 10.9734/bpi/ratmcs/v9/7445E. Disponível em: https://stm.bookpi.org/RATMCS-V9/article/view/13327. Acesso em: 2 jul. 2026.