Fixed small inconsistency.


git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@1571639 13f79535-47bb-0310-9956-ffa450edef68
Typo.


git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@1571640 13f79535-47bb-0310-9956-ffa450edef68