Dear Forum Members, The following article is urgently required by our faculty member for research purpose. If your library have access to this kindly send me the same and oblige. Pairs of two-level systems / U. Fano Rev. Mod. Phys. 55, 855 – Published 1 October 1983 http://journals.aps.org/rmp/abstract/10.1103/RevModPhys.55.855 With Regards Subir Kumar Mukherjee Central Library Ramakrishna Mission Vivekananda University PO Belur Math, Dist Howrah 711202 West Bengal, India Email: subir.mukh@gmail.com -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.