"1.2 Normative References reads in part:

• • • • • 
          J. Schneider, T. Kamiya, Efficient XML Interchange (EXI) Format 1.0, W3C Recommendation, 10 March 2011

The correct citation reads:

• • • • • EXI
          Efficient XML Interchange (EXI) Format 1.0 (Second Edition) , J. Schneider, T. Kamiya, D. Peintner, R. , Editors, W3C Proposed Edited Recommendation (work in progress), 22 October 2013, http://www.w3.org/TR/2013/PER-exi-20131022/ . Latest version available at http://www.w3.org/TR/exi/ .

Note the updated edition.
"