To cite package 'extRemes' in publications use:
Gilleland E and Katz RW (2011). “New software to analyze how extremes change over time.” Eos, 92(2), pp. 13–14.
Corresponding BibTeX entry:
@Article{, title = {New software to analyze how extremes change over time}, author = {Eric Gilleland and Richard W. Katz}, journal = {Eos}, year = {2011}, volume = {92}, number = {2}, pages = {13--14}, }