So what you are saying is that all the colouring properties of my edge-coloured graph G can be deduced from your completed graph G'. Jon Perry perry at globalnet.co.uk http://www.users.globalnet.co.uk/~perry/maths/ http://www.users.globalnet.co.uk/~perry/DIVMenu/ BrainBench MVP for HTML and JavaScript http://www.brainbench.com