Web of Science (ISI) (Sciences (1900+), Social Sciences (1898+), and Arts and Humanities (1975+). Search elements are author, journal or book title and year of publication. Key source does not have to be indexed in the database.
Citation searching in Advanced search mode with REFAUTH, might be reliable if the name is unique, like Wieschaus! One can view the citations of the key papers, and also link to related articles.
(1800's+) or APA PsycNET Use the Advanced Search mode and choose the Cited References tab. One may fill in author, title, or source words and/or a year. If the article is marked with "Cited in", one may view the citing document/paper.