麻义士（E.C.Machle），美国北长老会传教士，惠爱医院传教士，连州教案中妻子、女儿被杀。
（原文）
Canton， China，January 29th， 1912
This is to certify that Lo Po Yun is a fully qualified physician; having taken a full course of medicine under Dr.J.G.Kerr of Canton.He has acted as my assistant for two years and then as assistant to Dr.Dobson of Yeung Kong of A.P.In.Dr.Dolson being home on furlongh has no use for him at present.Should this interest you give him a trial and judge for yourself.He is a staunch Christian Instructor first class M.D.He is always faithful to his duties.I never had one more so.
Hoping he may find some one that can use him.
I am，Yours Sincerely，
E.C.Machle
P.S.I am at present not running a hospital but teaching medical students.
E.C.M.
（译文）
中国广州，1912年1月29日
兹证明卢宝云是一个完全合格的医生；在广州嘉·约翰博士指导下学完整套医学课程。他担任我的助理两年，后成为阳江美国长老会杜布森医师的助手。目前杜布森医生回家度假不再需要他。如果您感兴趣的话，给他一个机会并亲自考察他。他是一位一流的基督教医学博士教师，没有人比他更忠于职守了。
希望他能找到一个可以雇用他的人。
麻义士 谨上
附：我目前没有经营医院，而是从事医学教育。
麻义士