^ (2014). Daily Joy, National Geographic. ISBN 9781426209673 (revised Feb 2023)
^National Geographic Society (U. S.) (2014). Daily Joy: 365 Days of Inspiration: Photos and Wisdom to Lift Your Spirit, Random House Inc. BiggerBooks. ISBN 9781426209673 (revised Feb 2024)
^ (2013). Daily Joy: 365 Days of Inspiration: Photos and Wisdom to Lift Your SpiritECampus. ISBN 9781426209673 (revised Feb 2023)