=head1 DESCRIPTION
These functions are used to obtain temporary B<BIGNUM> variables from
-a B<BN_CTX> in order to save the overhead of repeatedly creating and
+a B<BN_CTX> (which can been created by using L<BN_CTX_new(3)|BN_CTX_new(3)>)
+in order to save the overhead of repeatedly creating and
freeing B<BIGNUM>s in functions that are called from inside a loop.
A function must call BN_CTX_start() first. Then, BN_CTX_get() may be