fix more authors bug (alshedivat#758)

* fix more authors bug

* fix

* add preview

Co-authored-by: Rohan Deb Sarkar <rohandebsarkar@gmail.com>

_bibliography/papers.bib

@@ -9,7 +9,7 @@ @book{einstein1956investigations
   author={Einstein, Albert},
   year={1956},
   publisher={Courier Corporation,},
-  preview={brownian-motion.gif},
+  preview={brownian-motion.gif}
 }
 
 @article{einstein1950meaning,
@@ -77,5 +77,6 @@ @book{przibram1967letters
   title={Letters on wave mechanics},
   author={Einstein, Albert and Schrödinger, Erwin and Planck, Max and Lorentz, Hendrik Antoon and Przibram, Karl},
   year={1967},
-  publisher={Vision}
+  publisher={Vision},
+  preview={wave-mechanics.gif}
 }

_layouts/bib.html

@@ -103,12 +103,12 @@
                 class="more-authors"
                 title="click to view {{more_authors_hide}}"
                 onclick="
-                  var element = $('span.more-authors');
+                  var element = $(this);
+                  element.attr('title', '');
                   var more_authors_text = element.text() == '{{more_authors_hide}}' ? '{{more_authors_show}}' : '{{more_authors_hide}}';
                   var cursorPosition = 0;
                   var textAdder = setInterval(function(){
                     element.text(more_authors_text.substring(0, cursorPosition + 1));
-                    element.attr('title', '');
                     if (++cursorPosition == more_authors_text.length){
                       clearInterval(textAdder);
                     }