R. Mathu Pritha, and A. Amutha. “Minimum Tree T-Spanners on Fuzzy Ratio Labelled General Graphs - NP Complete”. Utilitas Mathematica 122, no. 2 (September 18, 2025): 1110–1130. Accessed May 7, 2026. https://utilitasmathematica.com/index.php/Index/article/view/2823.