id	domain	url
ejnm-154	doi.org	https://doi.org/10.15218/ejnm.2021.08
ejnm-154	doi.org	https://doi.org/10.15218/ejnm.2021.08
ejnm-154	doi.org	https://doi.org/10.15218/ejnm.2021.08
ejnm-154	doi.org	https://doi.org/10.15218/ejnm.2021.08
ejnm-154	doi.org	https://doi.org/10.15218/ejnm.2021.08
ejnm-154	doi.org	https://doi.org/10.15218/ejnm.2021.08
ejnm-154	www.surveysystem.com	https://www.surveysystem.com/sscalc.htm
ejnm-154	doi.org	https://doi.org/10.15218/ejnm.2021.08
ejnm-154	www.who.int	https://www.who.int