Section 2328. Tax contract by the state

The state covenants with the
  purchasers and with all subsequent holders and transferees of  bonds  or
  notes  issued  by the authority pursuant to this title, in consideration
  of the acceptance of and payment for the bonds or notes, that the  bonds
  and  notes of the authority issued pursuant to this title and the income
  therefrom, and all moneys, funds and revenues pledged to pay  or  secure
  the  payment  of  such  bonds  or  notes shall at all times be free from
  taxation except for estate  taxes  and  taxes  on  transfers  by  or  in
  contemplation of death.