please answer the question as simple as you can .
” Using OSCOLA reference system ”
Recommended books : (1) Elspeth berry, Mathew J. Homewood, and Barbara Bogusz, Complete EU law text , cases and Materials (2nd ed, oxford university press , 2015 )
(2) Foster on EU law (5th ed, oxford univ press 2015)
(3) P Craig and G de Burca , EU law , Text, cases, Materials (6th ed, oxford university press , 2015 )
“please answer the question as simple as you can ”
Explain the principles of direct, indirect and incidental effect of European Union Directives and member state liability and critically consider why the Court of Justice felt it necessary to develop these principles