Name of the reference sytle

Can anyone tell me the name of the following reference style:

In text: [BAL 05] 

Bibliography: [BAL 05] BALANIS C., Antenna Theory: Analysis and Design, Wiley, 2005.

was duplicate post: 

see https://community.endnote.com/t5/EndNote-Styles-Filters-and/Name-of-the-reference-style/m-p/150978