URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_________::5579d208f2dc3c4e53c38fa33c81dc44https://doi.org/10.1080/00377310109517634
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_________::086372a01e431c2c4c7b21499850e7fehttps://doi.org/10.1007/bf02128544