It is not unusual for Beethoven to come up with four different versions of a single movement. His sketchbooks show that as he adjusted and fashioned each individual theme, the entire movement would undergo transformation. However, these transitional forms are usually only notated in the form of rough sketches. The pressing deadlines for his opera Fidelio’s premiere and later revival, resulted in Beethoven committing himself fully to paper before he was truly ready. The result is that instead of a single work and numerous incomplete sketches (the norm with Beethoven), we encounter four completed compositions, each of which suggests that the others are "incomplete." In the 19th century, the musicologist Nottebohm attempted to describe the overtures in evolutionary terms, and most latter day researchers still try to place them within a single chain of development. Their conclusions though are not entirely unanimous. Thus the Leonora overture No. 1 – with its freer form, and quotation of Florestan’s prison aria, and the liberation music – can equally be placed before Leonora No. 2 and No. 3 (as their freer structured predecessor) and after them (regarding it as a progression leading to the Fidelio overture which chooses a more neutral, less dramatic approach). The relationship between Leonora No. 2 and No. 3 (which also became very popular as an independent work) is unambiguous. The first was performed at the November 20th 1805 premiere, while the second was first heard on March 19th, 1806 at the opera’s revival. Thus, No. 3 realises the obvious aim of Leonora No. 2 in a more enclosed, dramatically more condensed form. No. 2 – in contrast to the symphonic character of Leonora No. 3, which virtually divorces itself from its original utilitarian function as an overture – is constructed with greater freedom: the slow introduction is unusually long, and the liberating trumpet fanfare (which again differs from No. 3, in that it is not an accurate quotation from the opera) is only heard at the end of the overture, nor is it followed by a return of the fast section.