"Nana" author (4)
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">nana author</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for zola that I've seen before include "French author of Germinal" , "See 15" , "19th-century French novelist" , "Emile --, French author" , "Fr. novelist (Germinal)" .)