http://library.bids.org.bd/cgi-bin/koha/opac-search.pl?q=ccl=au%3A%22Zahid%2C%20Hasan.%22&format=rss2 2 0 500 ISBN http://library.bids.org.bd/cgi-bin/koha/opac-detail.pl?biblionumber=60117 Dhaka : Published by the Director General, Department of Environment, 2002 . 32p.; , "Published on the Occasion of the World Environment Day, 5 June 2002." 27cm..

]]> http://library.bids.org.bd/cgi-bin/koha/opac-detail.pl?biblionumber=60117 ISBN http://library.bids.org.bd/cgi-bin/koha/opac-detail.pl?biblionumber=60180 Dhaka : Director General Department of Environment, 2000 . 105p.: , "Published on the Occasion of the World Environment Day, 5 June 2000" 27cm..

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