Is the Individual Work Performance Questionnaire (IWPQ) open and free to use for research or is it licensed and copyrighted?

I am really interested in using the Individual Work Performance Questionnaire (IWPQ) by Koopmans et al., (2013; 2014). However, I am unsure if I can freely use by citing the author it or if it is...

12 November 2021 7,281 3 View