To cite package 'ptw' in publications use:

Bloemberg, T. G. et al. (2010) "Improved Parametric Time Warping for Proteomics", Chemometrics and Intelligent Laboratory Systems, 104 (1), 65-74

Wehrens, R. et al. (2015) "Fast parametric warping of peak lists", Bioinformatics, in press.

Corresponding BibTeX entries:

    title = {Improved Parametric Time Warping for Proteomics},
    author = {Tom G. Bloemberg and Jan Gerretzen and Hans J. P. Wouters
      and Jolein Gloerich and Maurice {van Dael} and Hans J. C. T.
      Wessels and Lambert P. {van den Heuvel} and Paul H. C. Eilers and
      Lutgarde M. C. Buydens and Ron Wehrens},
    year = {2010},
    journal = {Chemometrics and Intelligent Laboratory Systems},
    volume = {104},
    number = {1},
    pages = {65-74},
    title = {Fast parametric warping of peak lists},
    author = {Ron Wehrens and Tom G. Bloemberg and Paul H. C. Eilers},
    year = {2015},
    journal = {Bioinformatics},
    doi = {10.1093/bioinformatics/btv299},