Smith, Fran; Himmel, Shiela. Changing the Way We Die: Compassionate End of Life Care and The Hospice Movement (англ.). — Berkeley, California: Cleis Press[англ.], 2013. — P. 23. — ISBN 9781936740604. — OCLC839388370.
Marks, Paul; Sterngold, James. On the Cancer Frontier: One Man, One Disease, and a Medical Revolution (англ.). — PublicAffairs[англ.], 2014. — P. 91. — ISBN 1610392523.
Smith, Fran; Himmel, Shiela. Changing the Way We Die: Compassionate End of Life Care and The Hospice Movement (англ.). — Berkeley, California: Cleis Press[англ.], 2013. — P. 23. — ISBN 9781936740604. — OCLC839388370.