tiny fix in tree documentation

alib2data/src/tree/ranked/PrefixRankedPattern.h

@@ -100,7 +100,7 @@ public:
 	explicit PrefixRankedPattern ( common::ranked_symbol < SymbolType, RankType > subtreeWildcard, ext::vector < common::ranked_symbol < SymbolType, RankType > > data );
 	/**
-	 * \brief Creates a new instance of the pattern based on the PrefixRankedTree. The linear representation is copied from tree. Alphabet as well. Subtree wildcard are defaultly constructed.
+	 * \brief Creates a new instance of the pattern based on the PrefixRankedTree. The linear representation is copied from tree. Alphabet as well. Subtree wildcard is defaultly constructed.
 	 *
 	 * \param tree representation of a tree.
 	 */