(Adds maturity, price guidance, timing information.) By Mark Brown Of DOW JONES NEWSWIRES LONDON (Dow Jones)--OeBB Infrastructur AG, Austria's government-guaranteed railway infrastructure agency, has hired Citigroup Inc., Erste Group, HSBC Holdings PLC and Morgan Stanley to run a planned euro-denominated benchmark bond, one of the banks said Monday. The bond will have a 15-year maturity, and price guidance is in the area of 55 basis points over midswaps. The issuer is rated Aaa by Moody's Investors Service Inc. and AAA by Standard & Poor's Corp. Order books are open and pricing is expected later Monday. -By Mark Brown, Dow Jones Newswires; + 44 (0)207 842 9485; [email protected] (END) Dow Jones Newswires June 21, 2010 05:00 ET (09:00 GMT)