These are two sequels to the Rescuers animated series, suggested and based on the best-selling Margery Sharp "Rescuers" novels.
Just so you know, the novel are nine:
Miss Bianca in the Salt Mines
Miss Bianca in the Orient
Miss Bianca in the Antarctic
Miss Bianca and the Bridesmaid
Bernard the Brave
Bernard into Battle
All of them are treasures of modern literature and should not be absent in any decent bookshelf or library.