APA   Click to copy
Greiff, S., & Fischer, A. (2013). Measuring complex problem solving. An educational application of psychological theories. Journal for Educational Research Online, 5, 34–53. https://doi.org/10.25656/01:8019

Chicago/Turabian   Click to copy
Greiff, S., and A Fischer. “Measuring Complex Problem Solving. An Educational Application of Psychological Theories.” Journal for Educational Research Online 5 (2013): 34–53.

MLA   Click to copy
Greiff, S., and A. Fischer. “Measuring Complex Problem Solving. An Educational Application of Psychological Theories.” Journal for Educational Research Online, vol. 5, 2013, pp. 34–53, doi:10.25656/01:8019.

@article{greiff2013a,
  title = {Measuring complex problem solving. An educational application of psychological theories},
  year = {2013},
  journal = {Journal for Educational Research Online},
  pages = {34-53},
  volume = {5},
  doi = {10.25656/01:8019},
  author = {Greiff, S. and Fischer, A}
}