APA
Europa Publications (London), . (1998). The World of learning, 1999. London: Europa.
Chicago
Europa Publications (London), . 1998. The World of learning, 1999. London: Europa.
Harvard
Europa Publications (London), . (1998). The World of learning, 1999. London: Europa.
MLA
Europa Publications (London), . The World of learning, 1999. London: Europa. 1998.