It depends what you mean by "sell". If you mean "Can I sell it as if I had created it?" then NO - you cannot. Most open source software does not allow you to sell it except where you have added a significant piece of functionality and you are charging ONLY for that and also, for the reasonable cost of transferring the code to a CD / DVD and the cost of posting. They do NOT allow you to sell software that they have made freely available under open source.