APA-ийн эшлэл(7 дахь хэвлэлт)

ebrary, Inc, & Okauru, I. O. (2012). Federal inland revenue service and taxation reforms in democratic Nigeria. Safari Books.

Чикаго-гийн эшлэл (17 дахь хэвлэлт)

ebrary, Inc, ба Ifueko Omoigui Okauru. Federal Inland Revenue Service and Taxation Reforms in Democratic Nigeria. Ibadan, Nigeria: Safari Books, 2012.

MLA -ийн эшлэл (9 дэх хэвлэлт)

ebrary, Inc, ба Ifueko Omoigui Okauru. Federal Inland Revenue Service and Taxation Reforms in Democratic Nigeria. Safari Books, 2012.