Adam L. Alter and Hal E. Hershfield, “People Search for Meaning When They Approacha New Decade in Chronological Age,” Proceedings of the National Academy of Sciences 111, no. 48 (2014): 17066–17070. Критику некоторых данных и выводов Олтера и Хершфилда см.: Erik G. Larsen, “Commentary On: People Search for Meaning When They Approach a New Decade in Chronological Age,” Frontiers in Psychology 6 (2015): 792.