北伐后期 ,为保证南北通邮 ,南北双方进行了近半年的艰苦谈判。本组史料对双方交涉的过程有一定反应 ,可供研究者参考。 In the latter part of the Northern Expedition, both sides conducted arduous negotiations for nearly six months in order to ensure postal communication between the North and the South. This group of historical data on the process of negotiation between both parties have a certain response, for researchers reference.