noun
BAD : In reference to your letter of 6th September, I am pleased to confirm that the books have now arrived.
GOOD : With reference to your letter of 6th September, I am pleased to confirm that the books have now arrived.
◆◆◆
with reference to sth (NOT in ): 'With reference to your recent article in Amateur Gardening , there are one or two questions that I would like to ask.'
See also REGARD 1 (↑ regard ), REGARDING (↑ regarding )