1. Lecturer, Bartlett School of Construction and Project Management, Univ. College London, London WC1E 7HB, UK (corresponding author). ORCID: .
2. Senior Quantity Surveyor, Costain Group, Ingwell Hall, Moor Row, Cumbria CA24 3JZ, UK.
3. Associate Professor, Dept. of Mathematics, Universidad de los Andes, Bogota 111711, Colombia. ORCID: .