You must overcome any shyness and have a conversation with the librarian, because he can offer you reliable advice that will save you much time. You must consider that the librarian (if not overworked or neurotic) is happy when he can demonstrate two things: the quality of his memory and erudition and the richness of his library, especially if it is small. The more isolated and disregarded the library, the more the librarian is consumed with sorrow for its underestimation. A person who asks for help makes the librarian happy.