Nuclear cross sections between charged particles at stellar energies are among the faintest to be measured in nuclear physics. In order to overcome the experimental problems connected to these measurements, indirect methods where proposed and used in many experiments over the last decades. One of these, the Trojan Horse method, is based on the Quasi-Free reaction mechanism and proved to be particularly flexible and reliable and it allowed for the measurement of the cross sections of various reactions of astrophysical interest. The use and reliability of indirect methods become even more important when reactions induced by Radioactive Ion Beams are considered. As an example we will report here on the first measurement of 18 F(p,α) 15 O process in Nova conditions by applying the Trojan Horse method to the 18 F(d,α 15 O)n reaction. In order to establish the reliability of such an approach, the Treiman-Yang criterion is an important test and it will also be addressed in this paper.