Question: Who wrote a biography of the jazz musician that lived his adult life as a man, but was assigned female at birth?

Context paragraphs:
Cam Lyman: Cam Lyman (September 4, 1932 – sometime between 1987–1995), born Camilla Lowell Lyman in Westwood, Massachusetts, was a multimillionaire breeder of champion Clumber Spaniels who notably died under mysterious circumstances.  He was assigned female at birth.  The Independent reported, however, that, as an adult, Lyman was "known to acquaintances as a man" and cultivated "a male identity."  Lyman's family members, however, have contended that there's no evidence that Lyman ever received sexual reassignment surgery and that therefore he should still be considered a woman.  Lyman disappeared in 1987 and was declared dead in 1995.

Diane Middlebrook: Diane Helen Wood Middlebrook (April 16, 1939 – December 15, 2007) was an American biographer, poet, and teacher.  She taught feminist studies for many years at Stanford University.  She is best known for critically acclaimed biographies of poets Anne Sexton and Sylvia Plath (along with Plath's husband Ted Hughes), and jazz musician Billy Tipton.  Middlebrook was preparing a biography of the Roman poet Ovid, to be published in 2008.  Her death brought that project to a close.

Transmasculine: Transmasculine is an umbrella term describing individuals who were assigned female at birth but identify on the male side of the gender spectrum.  A transmasculine individual may identify with many aspects of masculinity but not wish to describe themselves as "a man", and so may choose to behave in ways that are typically associated with women.

Trans man: A trans man (sometimes trans-man or transman) is a man who was assigned female at birth.  The label of transgender man is not always interchangeable with that of transsexual man, although the two labels are often used in this way.  "Transgender" is an umbrella term that includes different types of gender variant people (including transsexual people).  Many trans men choose to undergo surgical or hormonal transition, or both (see sex reassignment therapy), to alter their appearance in a way that aligns with their gender identity or alleviates gender dysphoria.

Transmasculine reproduction: Transmasculine reproduction is when an individual with a masculine gender identity, who was born with biologically female reproductive organs, conceives and births a child.  Transmasculine individuals were assigned female at birth, but identify more on the male side of the gender spectrum than on the female side.  These individuals may identify with some stereotypically masculine behaviors and gender performances, but may not necessarily identify with all aspects of masculinity or refer to themselves as “a man”.  They are also born with mammary glands and milk ducts, so in most cases it is also possible for them to breastfeed or “chest feed” their children even if they have had their breast surgically removed.  Transmasculine reproduction is a matter of sexual and reproductive health, but transmasculine individuals commonly deal with lack of cooperation from health care professionals when attempting to seek medical attention for stereotypically “woman’s health issues”.

Karl M. Baer: Karl M. Baer (20 May 1885 – 26 June 1956) was a German-Israeli author, social worker, reformer, suffragette and Zionist.  Assigned female at birth and named Martha Baer he became, in December 1906, one of the first people to undergo sex-change surgery, and one of the first, in January 1907, to gain full legal recognition of his gender identity and to have a new birth certificate issued reflecting his new gender.  Baer wrote notes for sexologist Magnus Hirschfeld on his experiences growing up as a girl while feeling inside that he was male.  Together they developed these notes into the semi-fictional, semi-autobiographical "Aus eines Mannes Mädchenjahren" ("Man's Years as a Young Girl") (1907) which was published under the pseudonym N.O. Body.  Baer also gained the right to marry and did so in October 1907.

Suicide of Blake Brockington: Blake Brockington (May 14, 1996 – March 23, 2015) was an American transgender man (assigned female at birth) whose suicide attracted international attention.  He had previously received attention as the first openly transgender high school homecoming king in North Carolina, and had since been advocating for LGBT youth, the transgender community, and against police brutality.

Joseph Lobdell: Joseph Lobdell (born in 1829 as Lucy Ann Lobdell), was a 19th century person assigned female at birth who lived as a man for sixty years.  20th-century scholars have labeled Lobdell a lesbian; others have argued that Lobdell was really a transgender man.  An 1877 "New York Times" article referred to Lobdell's life as "one of the most singular family histories ever recorded."  Writer William Klaber wrote an historical novel, "The Rebellion of Miss Lucy Ann Lobdell", which was based on Lobdell's life.

Bigender: Bigender, bi-gender or dual gender is a gender identity that includes any two gender identities and behaviors, possibly depending on context.  Some bigender individuals express two distinct "female" and "male" personas, feminine and masculine respectively; others find that they identify as two genders simultaneously.  It is recognized by the American Psychological Association (APA) as a subset of the transgender group.  A 1999 survey conducted by the San Francisco Department of Public Health observed that, among the transgender community, less than 3% of those who were assigned male at birth and less than 8% of those who were assigned female at birth identified as bigender.

Billy Tipton: William Lee Tipton (December 29, 1914 – January 21, 1989) was an American jazz musician and bandleader.  He is also notable for the postmortem discovery that, although he lived his adult life as a man, he was assigned female at birth.

Supporting paragraphs: Diane Middlebrook Billy Tipton
Answer: Diane Helen Wood Middlebrook