https://kohalibrary.pids.gov.ph//cgi-bin/koha/opac-search.pl?q=ccl=au%3A%22Card%2C%20David.%22%20and%20su-to%3ALabor%20economics%20and%20au%3AAshenfelter%2C%20Orley.&format=rss2 3 0 100 ISBN 444878580 https://kohalibrary.pids.gov.ph//cgi-bin/koha/opac-detail.pl?biblionumber=3874 By Ashenfelter, Orley.. Amsterdam [etc.] : North-Holland, 2006 . 3 v. in 5 (xxii, 3630, 83 p.) : ill. ; 25 cm. 444878580

]]> https://kohalibrary.pids.gov.ph//cgi-bin/koha/opac-detail.pl?biblionumber=3874 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

]]> https://kohalibrary.pids.gov.ph//cgi-bin/koha/opac-detail.pl?biblionumber=3875 ISBN 444501894 https://kohalibrary.pids.gov.ph//cgi-bin/koha/opac-detail.pl?biblionumber=3876 By Ashenfelter, Orley.. Amsterdam [etc.] : North-Holland, 2003 . 3 v. in 5 (xxii, 3630, 83 p.) : ill. ; 25 cm. 444501894

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