The National Park Service Civil War Regimental History
contains the
19th Regiment, Texas Cavalry (Burford's).

Sifakis' 'Compendium of the Confederate Armies'
notes the the first commander of the
Texas 19th Cavalry Regiment
was Nathaniel M. Burford, Colonel.

The Handbook of Texas Online has a biography of
Nathaniel Macon Burford
http://www.tsha.utexas.edu/handbook/online/articles/view/BB/fbu27.html
which contains the following
" In 1862 he received a commission as colonel and
raised a regiment from Dallas, Kaufman, Ellis, Hill,
Navarro, McLennan, and Parker counties. This regiment,
designated the Nineteenth Texas Cavalry, was ordered
to Arkansas, where it joined a brigade forming under
Col. William Henry Parsons. The Nineteenth Texas
served the entire war in the Trans-Mississippi
Department, generally under the command of Lt. Col.
Benjamin W. Watson or Maj. John B. Williams rather
than Colonel Burford. After the Red River campaign
in 1864 Burford offered his resignation, admitting
that he did not possess the ability to lead troops
in combat. His commanding officers agreed, commended
his patriotism, and accepted the resignation."