An Article in a Web Magazine. Provide the author name, article name in quotation marks, title of the Web magazine in italics, publisher name, publication date, medium of publication, and the date of access. Remember to use n.p. if no publisher name is available and n.d. if no publishing date is given.
The majority of viruses have capsids with either helical or icosahedral structure. Some viruses, such as bacteriophages, have developed more complicated structures due to constraints of elasticity and electrostatics.
Another classification uses the geometrical shape of their capsid (often a helix or an icosahedron) or the virus's structure (e.g. presence or absence of a lipid envelope). Viruses range in size from about 30 nm to about 450 nm, which means that most of them cannot be seen with light microscopes.