Purcell and his colleagues worked with public health agencies in Los Angeles and Orange County, California, as well as in Baltimore and Hawaii to round up and test 80 rats.

• 罗伯特.；普尔塞和同僚一起和加州洛杉矶郡；橙县;夏威夷;马里兰州的鲍特摩的公共卫生部门联手对80只老鼠进行了试验