To cite onlineforecast in publications use:

Bacher P, Madsen H, Nielsen HA, Perers B (2013). “Short-term heat load forecasting for single family houses.” Energy and Buildings, 65(0), 101-112. doi: 10.1016/j.enbuild.2013.04.022, https://onlineforecasting.org.

Corresponding BibTeX entry:

  @Article{,
    title = {Short-term heat load forecasting for single family
      houses},
    author = {Peder Bacher and Henrik Madsen and Henrik Aalborg Nielsen
      and Bengt Perers},
    journal = {Energy and Buildings},
    year = {2013},
    volume = {65},
    number = {0},
    pages = {101-112},
    doi = {10.1016/j.enbuild.2013.04.022},
    url = {https://onlineforecasting.org},
  }