Hacioglu, IlhanMichael, T.S.Ozdemir, Serhat2025-01-272025-01-2720141081-3810https://doi.org/10.13001/1081-3810.3008https://hdl.handle.net/20.500.12428/12930Fletcher asked whether there is a (0, 1)-matrix of order greater than 3 whose square is a regular tournament matrix. We give a negative answer for a special class of regular tourna- ment matrices: There is no (0, 1)-matrix of order greater than 3 whose square is a doubly regular tournament matrix. © 2015, Electronic Journal of Linear Algebra. All rights reserved.eninfo:eu-repo/semantics/openAccessDoubly regular tournament; Matrix square root; Tournament matrixArticle281798210.13001/1081-3810.30082-s2.0-84981216436Q3