https://gallica.bnf.fr/ark:/12148/bd6t54340212h/f8.double.r=tremblement%20dans%20l'%C3%A8criture]]> https://books.google.it/books/about/Praktisches_Lehrbuch_der_Graphologie_nac.html?id=j-VWAAAAYAAJ&redir_esc=y]]>