Scholary papers describing the methodology

The multcomp package implements multiplicity-adjusted tests and simultaneous confidence intervals for linear combinations of model parameters using methodology described in Hothorn, Bretz, and Westfall (2008) and the book by Bretz, Hothorn, and Westfall (2010).

References

[1] T. Hothorn, F. Bretz and P. Westfall. “Simultaneous Inference in General Parametric Models”. In: Biometrical Journal 50.3 (2008), pp. 346–363. DOI: 10.1002/bimj.200810425.

[2] F. Bretz, T. Hothorn and P. Westfall. Multiple Comparisons Using R. Boca Raton, Florida, USA: Chapman \& Hall/CRC Press, 2010. ISBN: 978–1–58488–574–0.