A modified modeling approach and a heuristic procedure for the multi-mode resource constrained project scheduling problem with activity splittingFatemeh Faghih-Mohammadi, Abbas Seifi and Mohammad Khalighi-SikaroudiRAIRO-Oper. Res., 50 1 (2016) 91-118DOI: https://doi.org/10.1051/ro/2015014