Thank you all for your information. By the way, the two companies that I found that deal with frozen controls are the following:

 

Biocat (www.biocat.de)

Clinomics Biosciences, Inc.

   phone: (413) 447-1919  toll free 877-728-4967

   Darleen Zradi in Customer Service will help you with 

   custom orders. 

 

Mariko