Fuente: Familiar Letters on Chemistry (Londres, 1854)
Frases célebres de Justus von Liebig
Fuente: Chemische Briefe (1851) Texto completo http://www.archive.org/details/chemischebriefe00liebuoft, citado en Physical Chemistry in the Service of Medicine (1907), Wolfgang Pauli, p.71, Texto completo http://www.archive.org/details/cu31924000951792.
Fuente: Familiar Lectures on Chemistry (1843).
Original: «The progress of mankind is due exclusively to the progress of natural sciences, not to morals, religion or philosophy».
Fuente: Active Pharmaceutical Ingredients in Synthesis: Catalytic Processes in Research and Development. Autores Anthony J. Burke, Carolina Silva Marques, Nicholas J. Turner, Gesine J. Hermann. Editorial John Wiley & Sons, 2018. ISBN 9783527807246. p. 359. https://books.google.es/books?id=nvRlDwAAQBAJ&pg=PA359&dq=The+progress+of+mankind+is+due+exclusively+to+the+progress+of+natural+sciences,+not+to+morals,+religion+or+philosophy.+Justus+von+Liebig&hl=es&sa=X&ved=0ahUKEwig24yGt9zgAhV65-AKHT6eB-wQ6AEIKzAA#v=onepage&q=The%20progress%20of%20mankind%20is%20due%20exclusively%20to%20the%20progress%20of%20natural%20sciences%2C%20not%20to%20morals%2C%20religion%20or%20philosophy.%20Justus%20von%20Liebig&f=false
Fuente: Idea general de Justus von Liebig, anunciada en su famoso libro de 1840.
Fuente: Justus von Liebig: Autobiography, 257-358. Citado en William H. Brock, Justus Von Liebig (2002), 9.
Justus von Liebig: Frases en inglés
Familiar Letters on Chemistry, Tr. Blythe, 4th ed., London, 1859, p. 60 as quoted by John Theodore Merz, A History of European Thought in the Nineteenth Century Vol.1 http://books.google.com/books?id=xqwQAAAAYAAJ (1903).
Chemische Briefe (1851) Full Text http://www.archive.org/details/chemischebriefe00liebuoft (quote's translation probably by Martin H. Fischer); quoted in Physical Chemistry in the Service of Medicine (1907), Wolfgang Pauli, p. 71, tr. by Martin H. Fischer. Full Text http://www.archive.org/details/cu31924000951792.