Section 6. Investment in obligations of housing corporations indirectly guaranteed pursuant to the "Servicemen's Readjustment Act of 1944"

Subject  to such regulations and restrictions as the banking board finds
  to be necessary and proper, any bank, trust company or savings bank  may
  invest in obligations of any corporation organized under any law of this
  state  for  the purpose of acquiring, constructing, owning, maintaining,
  operating, selling or conveying  a  housing  project  or  projects  (not
  including  hotels but including accommodations for retail stores, shops,
  offices  and  other  community  services  reasonably  incident  to  such
  projects)  located  within this state, which obligations are (a) secured
  by a first mortgage lien on such project, or such part thereof,  as  was
  or  is  to  be  constructed  or  acquired  out  of  the proceeds of such
  obligations, either directly or by issue under an indenture of  mortgage
  from such corporation to a corporate trustee having its principal office
  in  this  state,  and  (b)  guaranteed  indirectly through the pledge as
  security therefor of obligations directly guaranteed under  title  three
  of  an  act  of  congress entitled the "Servicemen's Readjustment Act of
  1944", in an aggregate amount equal to at least thirty per centum of the
  principal amount of all sums advanced to such corporation under the loan
  instrument or indenture during the  period  of  construction  and,  upon
  completion,  to the extent of at least forty per centum of the principal
  amount of such obligations.