Making Choices series). Also, a few branching-path books were aimed at adults, ranging from business simulations to works of erotica. Mainstream fiction Barring the aforementioned works of Dennis Guerrier in the 1960s, one of the earliest examples of the form is the five-volume Barcelona, Maxima Discrecion series, which adapted the noir fiction genre to an interactive form. Published in the 1980s, this series was only available in Catalan and Spanish. Heather McElhatton published a bestselling gamebook for adults in 2007, called Pretty Little Mistakes: A Do-Over Novel. It was followed by a sequel titled Million Little Mistakes published in 2010. Some contemporary literary novels have used the gamebook format, including Kim Newman's Life's Lottery (1999) and Nicholas Bourbaki's If (2014). Education In 2011, McGraw-Hill Education began releasing adaptations of the original Choose Your Own Adventure titles as graded readers. The stories were retold in simplified language and re-organized plotlines, in order to make them easier for English as a second or foreign language readers to play. The choice format of gamebooks has proved to be popular with ESL teachers as a way to motivate reluctant students, target critical thinking skills, and organize classroom activities. Erotica Various erotic gamebooks have been published by major publishers. In 1994 Derrière la porte by Alina Reyes was published by Pocket Books France and Éditions Robert Laffont, and later translated into English for Grove Press and Weidenfeld & Nicolson (as Behind Closed Doors) and into Italian for Ugo Guanda Editore (as Dietro le porte). Melcher Media in 2003 packaged two "Choose-Your-Own-Erotic-Adventure" books for Penguin Books' Gotham Books imprint, including Kathryn in the City by Mary Anne Mohanraj, a well-known writer of erotica. Role-playing solitaire adventures Solitaire adventures were a parallel development. This type of book is intended to allow a single person to use the rules of a role-playing game to experience an adventure without need of a referee. The first role-playing game solitaire adventures to be published were those using the Tunnels & Trolls system, beginning with the book Buffalo Castle in 1976, making Tunnels & Trolls the first role-playing game to support solitaire play. Flying Buffalo released 24 solo adventure books (plus several pocket size adventures) in the period 1976–1993. A number of the adventures are still in print today. They were very successful among players of role-playing games and inspired many imitators. Another early role-playing game with solitaire modules made for it