Ángel Gutiérrez, Julio César, David Soler Fernández, and Antonio Hervás Jorge. 2012. “An Efficient Transformation of General Problem of Routes With Capacity on Mixed Graphs”. Revista Universidad EAFIT 39 (130): 87-97. https://publicaciones.eafit.edu.co/index.php/revista-universidad-eafit/article/view/913.