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Publication of NL18359CpublicationCriticalpatent/NL18359C/xx
B61G3/00—Couplings comprising mating parts of similar shape or form which can be coupled without the use of any additional element or elements
B61G3/10—Couplings comprising mating parts of similar shape or form which can be coupled without the use of any additional element or elements with coupling heads in the form of hook-like interengaging rigid jaws, e.g. "Willison" type