That is a good point. Kev...
I would have thought that a small extract for the purposes of illustration or discussion would not be a breach of copyright, provided that the author/publisher/copyright holder were properly identified.
In book reviews, for instance, quite long passages are sometimes quoted. The author/publisher. copyright holder benefits by the publicity which should sell more books.
Looking at an article by a copyright lawyer
http://janefriedman.com/2013/07/15/the-fair-use-doctrine/ I would think that a short quotation (or image of part of a score) would be fine. I quote a short extract from the article (my quotation being, on the written advice of the said lawyer, covered by the fair use doctrine!)
But please refer to the full article - the lawyer invites questions, too, by email.
Here it is:
The fair use doctrine is defined here. To bring your otherwise unauthorized use within the protection of the doctrine, there are two separate and important considerations. First, your use must be for “purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research.”
This is the first prong. If your use falls into one of these categories, then you move to the second prong of the test. A court will consider the following four factors to determine if your use is a fair use:
- the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes;
- the nature of the copyrighted work;
- the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and (emphasis added)
- the effect of the use upon the potential market for or value of the copyrighted work.
If your use falls into one of the enumerated categories AND you are able to prevail factually on at least two of the four second-prong factors, you might succeed in proving that your use is fair and thus not copyright infringement.
End of quotation.