Angela Royston. (2003). Heavy and Light (Heinemann First Library). Heinemann/Raintree.
Cita Chicago (17th ed.)Angela Royston. Heavy and Light (Heinemann First Library). Heinemann/Raintree, 2003.
Cita MLA (9th ed.)Angela Royston. Heavy and Light (Heinemann First Library). Heinemann/Raintree, 2003.
Atenció: Aquestes cites poden no estar 100% correctes.