TY  - COMP
A1  - James, D.
A1  - Hornik, K.
T1  - chron: Chronological objects which can handle dates and times. R package
Y1  - 2011
UR  - http://cran.r-project.org/web/packages/chron/index.html 
N1  - (Accessed January 16, 2013); 2.3-43

ER  -