Liên kết ngoài Leonhard von Blumenthal

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WikiPedia: Leonhard von Blumenthal http://cantic.bnc.cat/registres/CUCId/a12130801 http://select.nytimes.com/gst/abstract.html?res=F7... http://uli.nli.org.il/F/?func=direct&doc_number=00... http://data.bibliotheken.nl/id/thes/p067915051 http://archive.org/stream/menwhohavemadene01stra/m... http://www.archive.org/details/journalsoffieldm00b... http://en.wikisource.org/wiki/1911_Encyclop%C3%A6d... http://mak.bn.org.pl/cgi-bin/KHW/makwww.exe?BM=1&N... https://nla.gov.au/anbd.aut-an36046955 https://trove.nla.gov.au/people/1200684