Errata
  
   In the list of patents which expired on May 13, 1994, due to failure to
pay maintenance fees, in the OG of July 25, 1994, Patent Number Re.
33,633 should not have appeared since the fee was timely paid.
   
   In the list of patents which expired on January 15, 1995, due to failure
to pay maintenance fees, in the OG of March 28, 1995, Patent Number
4,636,977 should not have appeared since the fee was timely paid.
   
   In the list of patents which expired on September 29, 1995, due to
failure to pay maintenance fees, in the OG of December 5, 1995, Patent
Number 4,696,884 should not have appeared since the fee was timely paid.