id	domain	url
flr-777	doi.org	https://doi.org/10.14786/flr.v9i4.777
flr-777	ec.europa.eu	http://ec.europa.eu/research/swafs/pdf/pub_science_education/ki-na-26-893-en-n.pdf
flr-777	doi.dx.org	https://doi.dx.org/10.22318/cscl2018.1129
flr-777	www.jstor.org	www.jstor.org/stable/1177186
flr-777	www.socialstudies.org	http://www.socialstudies.org/standards
flr-777	www.socialstudies.org	https://www.socialstudies.org/standards/nationalstandards-preparation-social-studies-teachers