Yes sorry I was wrong. I agree it is 69. Here is the numbered list from the paper. I was assuming this was a numbering because it appears to be in order but closer scrutiny reveals it is not a 1 to N numbering but must be numbers to references since some numbers repeat and they are not all in order.
Linda M. Liau1*, Keyoumars Ashkan2, David D. Tran3, Jian L. Campian4, John E. Trusheim5, Charles S. Cobbs6, Jason A. Heth7, Michael Salacz8, Sarah Taylor8, Stacy D. D'Andre9, Fabio M. Iwamoto10, Edward J. Dropcho11, Yaron A. Moshel12, Kevin A. Walter13, Clement P. Pillainayagam14, Robert Aiken15, Rekha Chaudhary16, Samuel A. Goldlust17, Daniela A. Bota18, Paul Duic19, Jai Grewal59, Heinrich Elinzano20, Steven A. Toms20, Kevin O. Lillehei21, Tom Mikkelsen22, Tobias Walbert22, Steven R. Abram23, Andrew J. Brenner24, Steven Brem25, Matthew G. Ewend26, Simon Khagi26, Jana Portnow27, Lyndon J. Kim28, William G. Loudon29, Reid C. Thompson30, David E. Avigan31, Karen L. Fink32, Francois J. Geofroy33, Scott Lindhorst34, Jose Lutzky35, Andrew E. Sloan36, Gabriele Schackert37, Dietmar Krex37, Hans-Jorg Meisel38, Julian Wu39, Raphael P. Davis40, Christopher Duma41, Arnold B. Etame42, David Mathieu43, Santosh Kesari44, David Piccioni44, Manfred Westphal45, David S. Baskin46, Pamela Z. New46, Michel Lacroix47, Sven-Axel May48, Timothy J. Pluard49, Victor Tse50, Richard M. Green51, John L. Villano52, Michael Pearlman53, Kevin Petrecca54, Michael Schulder55, Lynne P. Taylor56, Anthony E. Maida58, Robert M. Prins1 Timothy F. Cloughesy1, Paul Mulholland57 and Marnix L. Bosch58