diff --git a/doc/src/sgml/ecpg.sgml b/doc/src/sgml/ecpg.sgml
index 18a7a86e2c8..a11ad8f06c5 100644
--- a/doc/src/sgml/ecpg.sgml
+++ b/doc/src/sgml/ecpg.sgml
@@ -3342,7 +3342,7 @@ interval *PGTYPESinterval_new(void);
        <para>
         Release the memory of a previously allocated interval variable.
 <synopsis>
-void PGTYPESinterval_new(interval *intvl);
+void PGTYPESinterval_free(interval *intvl);
 </synopsis>
        </para>
       </listitem>