A data frame with 36 observations on the following 5 variables.
treatments
a numeric vector
blocks
a factor with levels b1b2b3
period
a numeric vector
animal
a numeric vector
gain
a numeric vector
References
SANDERS W.L. and GAYNOR, P.J. Analysis of switchback data using Statistical Analysis System, Inc. Software. Journal of Dairy Science, 70.2186-2191. 1987.