Most modern versions are designed for the Enhanced Editions (EE) of Baldur's Gate, though some support the original "Tutu" conversion.
The most "useful paper" or primary documentation for this mod is found on the (G3) platform, which maintains and hosts these quest mods. Mod Title: Baldur's Gate Quest and Encounter (BGQE) Component: Undying Love Quest Developer: Jastey download-undying-v0-5-1
If your query was instead for a literal academic paper with "Undying" and "v0.5.1" (or similar versioning): Most modern versions are designed for the Enhanced
Guide-Tone Space: Navigating Voice-Leading Syntax in Tonal Jazz download-undying-v0-5-1