Yes, there are alternatives to Wikipedia.  The following are examples of authoritative subject encyclopedias available either electronically or in print.

Dictionary of Literary Biography. Detroit, Mich.: Gale Research Co., 1978- . MAIN Reference (Encyclopedia Case)  810.3 D554 Use index in latest volume to locate a specific author.   Available over the Internet, without the illustrations, as part of the Literature Resource Center

Stearns, Peter N. Encyclopedia of European Social History from 1350 to 2000. Detroit: Charles Scribner's Sons, 2001. Also in print at MAIN Reference 306.09403 E56

Grendler, Paul F. Encyclopedia of the Renaissance. New York: Scribner's, 1999. MAIN Reference (Encyclopedia Case) 940.2303 E56

Dewald, Jonathan. Europe 1450 to 1789: Encyclopedia of the Early Modern World. New York: Thomson Gale, 2004. MAIN Reference 940.2 E887

Horowitz, Maryanne Cline. New Dictionary of the History of Ideas. New York: Charles Scribner's Sons, 2005. Also in print at MAIN Reference (Encyclopedia case) 903 N532