Sparrho - Wikipedia
Scizzle are targeted towards biomedical sciences and solely recommend academic journal papers. List of academic databases and search engines "Sparrho's technology
Timeline of web search engines - Wikipedia
depth". September 15, 1997. Retrieved February 1, 2014. About Yandex — History of Yandex. Retrieved May 24, 2011. Archived copy. "The GnuHoo BooBoo". Slashdot