@BOOK{NAP6351, author = "Transportation Research Board", title = "Directions: A Simple Guidebook for Integrating Market and Customer Research into Transit Decision-Making to Become Customer Oriented", doi = "10.17226/6351", url = "https://nap.nationalacademies.org/catalog/6351/directions-a-simple-guidebook-for-integrating-market-and-customer-research", year = 1998, publisher = "The National Academies Press", address = "Washington, DC" }