Ibrahim Muter S. Ilker Birbil Kerem Bülbül Güvenç Sahin A note on "A LP-based heuristic for a time-constrained routing problem". 306-307 2012 221 Eur. J. Oper. Res. 2 https://doi.org/10.1016/j.ejor.2012.03.048 db/journals/eor/eor221.html#MuterBBS12