https://kohalibrary.pids.gov.ph//cgi-bin/koha/opac-search.pl?q=ccl=au%3A%22Layard%2C%20P.%20R.%20G.%22%20and%20su-to%3ALabor%20economics&format=rss2 3 0 100 ISBN 444878564 https://kohalibrary.pids.gov.ph//cgi-bin/koha/opac-detail.pl?biblionumber=3872 By Ashenfelter, Orley.. Amsterdam [etc.] : North-Holland, 2002 . 3 v. in 5 (xxii, 3630, 83 p.) : ill. ; 25 cm. 444878564

]]> https://kohalibrary.pids.gov.ph//cgi-bin/koha/opac-detail.pl?biblionumber=3872 ISBN "0444878580 " https://kohalibrary.pids.gov.ph//cgi-bin/koha/opac-detail.pl?biblionumber=3873 By Ashenfelter, Orley.. Amsterdam [etc.] : North-Holland, 2002 . 2 v. : ill. ; 25 cm. "0444878580 "

]]> https://kohalibrary.pids.gov.ph//cgi-bin/koha/opac-detail.pl?biblionumber=3873 ISBN 444878580 https://kohalibrary.pids.gov.ph//cgi-bin/koha/opac-detail.pl?biblionumber=3875 By Ashenfelter, Orley.. Amsterdam [etc.] : North-Holland, 2006 . 3 v. in 5 (xxii, 3630, 83 p.) : ill. ; 25 cm. 444878580

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