The application must disclose the invention in a manner sufficiently clear and complete for it to be carried out by a person skilled in the Art. The "person skilled in the art" for this purpose is considered to be the ordinary practitioner aware not only of the teaching of the application itself and the references therein, but also of what was common general knowledge in the art at the date of filing the application. He is assumed to have had at his disposal the means and the capacity for routine work and experimentation, which are normal for the technical field in question. As "common general knowledge" can generally be considered the information contained in basic handbooks, monographs and textbooks on the subject in question (see T 171/84, OJ 4/1986, 95). As an exception, it can also be the information contained in patent specifications or scientific publications, if the invention lies in a field of research which is so new that the relevant technical knowledge is not yet available from textbooks (see T 51/87, OJ 3/1991, 177). Sufficiency of disclosure must be assessed on the basis of the application as a whole, including the description, claims and drawings, if any. The provisions relating to the content of the description are set out in Rule 27. The purpose of the provisions of Art. 83 and Rule 27 is: