
p. 69 http://books.google.com/books?id=HXQKAQAAQBAJ&lpg=PP1&pg=PA69 of Vol. II of The Complete and Authoritative Edition, 2013, University of California Press
Autobiography of Mark Twain, Vol. 2 (2013)
In p. 163.
Sources, The Yoga Darsana Of Patanjali With The Sankhya Pravacana Commentary Of Vyasa
p. 69 http://books.google.com/books?id=HXQKAQAAQBAJ&lpg=PP1&pg=PA69 of Vol. II of The Complete and Authoritative Edition, 2013, University of California Press
Autobiography of Mark Twain, Vol. 2 (2013)
Source: The Functions of the Executive (1938), p. 19 (in 1968 edition)
Voltaire (1916)
The Book of the Staff, translated by Paul M. Cobb (Penguin: 2008), p. 245
Source: Problems and theories of philosophy, 1949, p. 154, as cited in Łukasiewicz, 2016.
“A happy life consists not in the absence, but in the mastery of hardships.”
The Simplest Way to be Happy (1933)