Title A proof of a conjecture on the differential of a subcubic graph Type of Research Article Keywords A proof of a conjecture on the differential of a subcubic graph Abstract A proof of a conjecture on the differential of a subcubic graph Researchers Rana Khoeilar (First Researcher)، hossein karami (Second Researcher)، Mustapha Chellali (Third Researcher)، Seyed Mahmoud Sheikholeslami Kavkani (Fourth Researcher)، Lutz Volkmann (Fifth Researcher)