We refer you to the prefix circular of our mr. t. r., announcing the establishment of our firm In this city. 请参照我们公司T.R.先生的介绍函,该函通知本公司将于本市开业。
First order nonlinear non-holonomic mechanical systems having variable mass was deduced from the T. R. Kane's equation for the mechanical systems having variable mass. 本文从变质量力学系统的Kane方程,推出了变质量一阶非线性非完整系统的拉格朗日方程。