Yopp JM, Deal AM, Nakamura ZM, Park EM, Edwards T, Wilson DR, Biesecker B, Rosenstein DL. Psychological and parental functioning of widowed fathers: the first two years. J Fam Psychol. 2019 Aug;33(5):565-74. doi: 10.1037/fam0000528
McKenna SP, Doward LC. How should we measure quality of life in ankylosing spondylitis? Rheumatol Pract. 2008;6(2):12-4.