To cite strucchange in publications use:

Zeileis A, Leisch F, Hornik K, Kleiber C (2002). “strucchange: An R Package for Testing for Structural Change in Linear Regression Models.” Journal of Statistical Software, 7(2), 1–38. doi:10.18637/jss.v007.i02.

If methods related to breakpoints() are used also cite:

Zeileis A, Kleiber C, Krämer W, Hornik K (2003). “Testing and Dating of Structural Changes in Practice.” Computational Statistics \& Data Analysis, 44(1–2), 109–123. doi:10.1016/S0167-9473(03)00030-6.

If methods related to gefp() and efpFunctional() are used also cite:

Zeileis A (2006). “Implementing a Class of Structural Change Tests: An Econometric Computing Approach.” Computational Statistics \& Data Analysis, 50(11), 2987–3008. doi:10.1016/j.csda.2005.07.001.

Corresponding BibTeX entries:

  @Article{,
    title = {strucchange: An R Package for Testing for Structural
      Change in Linear Regression Models},
    author = {Achim Zeileis and Friedrich Leisch and Kurt Hornik and
      Christian Kleiber},
    journal = {Journal of Statistical Software},
    year = {2002},
    volume = {7},
    number = {2},
    pages = {1--38},
    doi = {10.18637/jss.v007.i02},
  }
  @Article{,
    title = {Testing and Dating of Structural Changes in Practice},
    author = {Achim Zeileis and Christian Kleiber and Walter Kr\"amer
      and Kurt Hornik},
    journal = {Computational Statistics \& Data Analysis},
    year = {2003},
    volume = {44},
    number = {1--2},
    pages = {109--123},
    doi = {10.1016/S0167-9473(03)00030-6},
  }
  @Article{,
    title = {Implementing a Class of Structural Change Tests: An
      Econometric Computing Approach},
    author = {Achim Zeileis},
    journal = {Computational Statistics \& Data Analysis},
    year = {2006},
    volume = {50},
    number = {11},
    pages = {2987--3008},
    doi = {10.1016/j.csda.2005.07.001},
  }