A manual for writers of research papers, theses, and dissertations, 7th edition - Kate L. Turabian 2007

Professional titles
Abbreviations
Part III. Style 20 spelling

Some individuals have civil, military, or religious titles such as the following along with their personal names. Many of these titles are conventionally abbreviated rather than spelled out in text when they precede and are treated as part of a personal name. Since they are all shortened forms of official (proper) titles, only the first letter is capitalized, and they are followed by periods.

Adm. - Admiral

Ald. - Alderman, Alderwoman

Atty. Gen. - Attorney General

Capt. - Captain

Col. - Colonel

Dist. Atty. - District Attorney

Dr. - Doctor

Fr. - Father

Gen. - General

Gov. - Governor

Hon. - Honorable

Lt. - Lieutenant

Lt. Col. - Lieutenant Colonel

Maj. - Major

Pres. - President

Rep. - Representative

Rev. - Reverend

Sen. - Senator

Sgt. - Sergeant

Sr. - Sister

St. - Saint

On first reference to an individual with such a title, use the abbreviation with the person's full name. (If you prefer, you may always spell out the titles, but do so consistently.) For subsequent references, you may usually give just the person's last name, but if you need to repeat the title (to distinguish two people with similar names, or as a disciplinary sign of respect), give the spelled-out title with the last name. Never use Reverend or Honorable except with a full name, in which case the title should be preceded by the word the.

Sen. Barack Obama

Senator Obama

Gen. Richard Myers

General Myers

Rev. Jane Schaefer

the Reverend Jane Schaefer

If you use one of these titles alone or after a personal name, it becomes a generic term and should be lowercased and spelled out.

the senator from Illinois

Myers served as a general

An exception to the general pattern is Dr. Use either the abbreviation Dr. before the name, or the official abbreviation for the degree (see 24.2.3), set off with two commas, after the name. Do not use both together.

Dr. Lauren Shapiro discovered the cause of the outbreak.

Lauren Shapiro, MD, discovered . . .

Dr. Shapiro discovered . . .

The doctor discovered . . .

In addition to academic degrees, here are a few other professional titles that may be abbreviated following a personal name. Such titles should be set off with commas, as in the examples above.

JP - justice of the peace

LPN - licensed practical nurse

MP - member of Parliament

SJ - Society of Jesus