"Perhaps most important,though, we can now field initial elements of the system to protect our forces in Europe and our allies roughly six to seven years earlier than the previous plan a fact made more relevant by continued delaysin the Czech and Polish ratification processes that have caused repeated slips in the timeline,".

VOA: standard.2009.09.17

Here he is in his paper and says at that time I decided that it was advantageous to find a more general system of the elements and here is my attempt.

他在论文中说，当时,我觉得发现更多,的元素的通用系统是很有用的,这就是我的计划。

麻省理工公开课 - 固态化学导论课程节选