Brendan enters the Clayton Books store intending to buy a copy of a book called 'The Tactical Use of Elephants in Warfare by the Ancient Greeks and Romans' which he has seen in the window. When he asks Carla, the shop assistant, she tells him that she has sold all the copies of the book and that even the copy in the window has already been sold. She suggests that Brendan might find something similar in the history section in the back of the shop.

Brendan looks through the shelves and finds a copy of the exact same book which was in the window and which he wishes to own. He takes it to Carla with the correct money but she still refuses to sell him the book.

Using Contract law principles only discuss whether Carla was legally entitled to refuse to sell the book.