The development of Planck has been supported by: ESA; CNES and CNRS/INSU-IN2P3-INP (France); ASI, CNR, and INAF (Italy); NASA and DoE (USA); STFC and UKSA (UK); CSIC, MICINN, JA and RES (Spain); Tekes, AoF and CSC (Finland); DLR and MPG (Germany); CSA (Canada); DTU Space (Denmark); SER/SSO (Switzerland); RCN (Norway); SFI (Ireland); FCT/MCTES (Portugal); and PRACE (EU). The authors thank N.Schartel, ESA XMM-Newton project scientist, for granting the DDT used for confirmation of SZ Planck candidates. The authors thank TUBITAK, IKI, KFU and AST for support in using RTT150; in particular we thank KFU and IKI for providing significant amounts of their observing time at RTT150. We also acknowledge the BTA 6 m telescope TAC for support of the optical follow-up project. The authors acknowledge the use of the INT and WHT telescopes operated on the island of La Palma by the Isaac Newton Group of Telescopes at the Spanish Observatorio del Roque de los Muchachos of the IAC; the NOT, operated on La Palma jointly by Denmark, Finland, Iceland, Norway, and Sweden,at the Spanish Observatorio del Roque de los Muchachos; the TNG, operated on La Palma by the Fundacion Galileo Galilei of the INAF at the Spanish Observatorio del Roque de los Muchachos; the GTC telescope, operated on La Palma by the IAC at the Spanish Observatorio del Roque de los Muchachos; and the IAC80 telescope operated on the island of Tenerife by the IAC at the Spanish Observatorio del Teide. Part of this research has been carried out with telescope time awarded by the CCI International Time Programme. The authors thank the TAC of the MPG/ESO-2.2m telescope for support of optical follow-up with WFI under Max Planck time. This research has made use of SDSS-III data. Funding for SDSS-III (http://www.sdss3.org/) has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and DoE. SDSS-III is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS-III Collaboration. This research has made use of the following databases: the NED and IRSA databases, operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the NASA; SIMBAD, operated at CDS, Strasbourg, France; SZ cluster database (http://szcluster-db.ias.u-psud.fr) and SZ repository operated by IDOC operated by IAS under contract with CNES and CNRS.