Looks can be deceiving - Underestimating the age of single white dwarfs due to binary mergers K. D. Temmink, S. Toonen, E. Zapartas, S. Justham and B. T. Gänsicke A&A, 636 (2020) A31 Published online: 10 April 2020 DOI: 10.1051/0004-6361/201936889