https://opac.cottonuniversity.ac.in/cgi-bin/koha/opac-search.pl?q=ccl=au%3A%22Gregory%2C%20Derek.%22&format=rss 4 0 50 ISBN:0-09-133121-8 https://opac.cottonuniversity.ac.in/cgi-bin/koha/opac-detail.pl?biblionumber=8161 By Gregory, Derek .. London : Hutchinson & Co , 1979 . 198p. : 21cm .. 0-09-133121-8

]]> https://opac.cottonuniversity.ac.in/cgi-bin/koha/opac-detail.pl?biblionumber=8161 ISBN: https://opac.cottonuniversity.ac.in/cgi-bin/koha/opac-detail.pl?biblionumber=29267 By Gregory, Derek .. London : Macmillan and Co. , 1994 . 294p. ; 22cm..

]]> https://opac.cottonuniversity.ac.in/cgi-bin/koha/opac-detail.pl?biblionumber=29267 ISBN:1-400051-3604-9 https://opac.cottonuniversity.ac.in/cgi-bin/koha/opac-detail.pl?biblionumber=51748 By Johnston, R.j.. U.K : Blackwell , 2005 . 958pg ; 15cm.. 1-400051-3604-9

]]> https://opac.cottonuniversity.ac.in/cgi-bin/koha/opac-detail.pl?biblionumber=51748 ISBN:978-1-4051-3287-9 https://opac.cottonuniversity.ac.in/cgi-bin/koha/opac-detail.pl?biblionumber=54310 By Gregory, Derek .. New York : John Wiley & Sons , 2009 . 1052pg ; 23cm.. 978-1-4051-3287-9

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