fix more authors bug (alshedivat#758)

* fix more authors bug

* fix

* add preview

Co-authored-by: Rohan Deb Sarkar <[email protected]>

Author: 2 people

_bibliography/papers.bib

@@ -47,9 +47,10 @@ @article{10.1145/3519022
 }
 
 @book{przibram1967letters,
-  bibtex_show={true},
-  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}
+  bibtex_show = {true},
+  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},
+  preview     = {wave-mechanics.gif}
 }