3Roland N. Mckean and Jacquelene M. Browning(1975), Externalities from Govenunent and Non- prdlt Sectors, Canadian Journal of Economics 8(4),Nov.
4Roland N Mckean and Jacquelene M Browning.“Externalities from Government and Non-profit Sectors,Canadian Journal of Economics Ⅷ”.no.4 November 1975,Printed in Canada.