@article { kerres_didactica,
	title = {A didactical framework for the design of blended learning arrangements},
	journal = {Journal for Educational Media},
	volume = {28},
	year = {2003},
	pages = {101{\textendash}114},
	publisher = {Universit{\"a}t St. Gallen},
	author = {Michael Kerres and de Witt, Claudia}
}
