The 3 references in paper Nicholas J. Cox, Christopher F. Baum () “Metadata for user-written contributions to the Stata programming language: extensions” / RePEc:tsj:stbull:y:2000:v:9:i:54:ip29.1

Jones B. and M. G. Kenward. 1989.Design and Analysis of Crossover Trials. London: Chapman and Hall.
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Ryan, P. 1998. Random allocation of treatments in blocks.Stata Technical Bulletin41: 43–46. Reprinted inStata Technical Bulletin Reprints, vol. 7, pp. 297–300. ——. 1999. Update to random allocation of treatments in blocks.Stata Technical Bulletin50: 36–37. STB categories and insert codes
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Inserts in /LRihtim Cad. Polat Han D:38 Address:249 Eramosa Road WestKadikoy Moorooduc VIC 393381320 ISTANBUL AustraliaTurkey Phone:+61 (0)3 5978 8329Phone:+90 (216) 414 19 58 Fax:+61 (0)3 5978 8623Fax:+30 (216) 336 89 23 Email:sa
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