small typo fixes and rewording of the citation sources paragraph
small typo fixes and rewording of the citation sources paragraph

Impactstory/total-impact-webapp,Impactstory/total-impact-webapp,total-impact/total-impact-webapp,total-impact/total-impact-webapp,Impactstory/total-impact-webapp,total-impact/total-impact-webapp,Impactstory/total-impact-webapp,total-impact/total-impact-webapp