Exhibit 16.1

 April 26, 2006

 Securities and Exchange Commission
 100 F Street, N.E.
 Washington, DC 20549

      We have read the  statements  made by the PS 401(k)  Profit  Sharing  Plan
(copy  attached),  which we  understand  will be filed  with the  United  States
Securities and Exchange  Commission,  pursuant to Item 4.01 of Form 8-K, as part
of the Plan's Form 8-K report dated April 21, 2006. We agree with the statements
concerning our Firm in such Form 8-K.

Very truly yours,

/s/ Link, Murrel & Company
---------------------------
Link, Murrel & Company