The answer is MLA bibliographic information. The bibliographic information of a certain article or book is what you should record on a biobliography card if you're using the index-card oragnizational system.
A bibliography card is an index card where you write down the information concerning the author and editiorial information of the source you are using. In research it helps you organize what you have already read so you can add this information later on and give credit to the author, avoiding plagiarism.
Therefore, on a bibliography card you must write the bibliographic information of the source. Data such as author, title, publication date, name of the editorial or journal that published it, are among the information the Modern Language Association (MLA) requires in a reference.