http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
The protective value of conspicuous signals is not impaired by shape, size, or position asymmetry
Martin Stevens, Sarah A. Castor-Perry, Jessica R.F. Price.
Vol. 20, no. 1 (January-February 2009), p. 96-102