Combinations with Exclusions

In a school, there are 10 different books available for a reading club. A group of students needs to select a combination of 3 books to read for the next month. Each book is unique, and the order in which they choose the books does not matter. However, they also have a special rule: if they choose the first book as 'Book A', they must then exclude 'Book B' from their selection. How many different combinations of books can the students select while adhering to this rule?