package bats by Martyn Plummer , Paul Gilbert package tseries and ar.ols by Adrian Trapletti stl code on netlib, presumably by the authors of R.B. Cleveland, W.S. Cleveland, J.E. McRae, and I. Terpenning, STL: A Seasonal-Trend Decomposition Procedure Based on Loess, Statistics Research Report, AT&T Bell Laboratories. Fortran package ts by B.D. Ripley, 1977--82, including starma.f which is Applied Statistics Algorithm AS154.