To cite CausalImpact in publications use:

Brodersen KH, Gallusser F, Koehler J, Remy N, Scott SL (2014). “Inferring causal impact using Bayesian structural time-series models.” Annals of Applied Statistics, 9, 247–274. http://research.google.com/pubs/pub41854.html.

Corresponding BibTeX entry:

  @Article{,
    title = {Inferring causal impact using {B}ayesian structural
      time-series models},
    author = {Kay H. Brodersen and Fabian Gallusser and Jim Koehler and
      Nicolas Remy and Steven L. Scott},
    journal = {Annals of Applied Statistics},
    year = {2014},
    volume = {9},
    pages = {247--274},
    url = {http://research.google.com/pubs/pub41854.html},
  }