What information is mandatory depends on the applied reference style, e.g. APA6 oder Chicago Style. The style even sets the number of authors listed maximum in the reference.

Usually, the mandatory information for journal/conference papers includes:

 - Author(s) name(s)
 - Title
 - Year
 - Journal/Conference name
 - Page number
 - DOI

The only real option to shorten anything is to use the abbreviations of journals/conferences. But the applied referency style might even prevent this trick.