The International Plant Names Index (IPNI) describes itself as "a database of the names and associated basic bibliographical details of seed plants, ferns and lycophytes." Coverage of plant names is best at the rank of species and genus. It includes basic bibliographical details associated with the names. Its goals include eliminating the need for repeated reference to primary sources for basic bibliographic information about plant names. The IPNI also maintains a list of standardized author abbreviations. These were initially based on Brummitt & Powell (1992), but new names and abbreviations are continually added.