Rúa Flechas, M., Arbeláez Restrepo, J. C. and Castro Beltrán, H. (2019) “Planning of Public Works Contracts in Colombia: Principle, Duty or Requirement? Obligatoriness and Consequences of its Inapplication”, Opinión Jurídica, 18(37), pp. 93–115. doi: 10.22395/ojum.v18n37a3.