Variation in English

Susan Conrad is an assistant professor in the Department of English and Program in Linguistics at Iowa State University. She is the co-author of Corpus Linguistics- Investigating Language Structure and Use (1998) and the Longman Grammar of Spoken and Written English (1999).
Douglas Biber is Regents' Professor of English (Applied Linguistics) at Northern Arizona University. His works include Variation Across Speech and Writing (1988), Dimensions of Register Variation- A Cross-Linguistic Comparison (1995), Corpus Liinguistics- Investigating Language Structure and Use (with Conrad and Reppen, 1998) and the co-authored Longman Grammar of Spoken and Written English (1999).