1.  Gust Skordas, ed.  1968.  The Early Settlers of Maryland: an Index to Names of Immigrants, Compiled from Records of Land Patents, 1633-1680, in the Hall of Records, Annapolis, Maryland.  Genealogical Publ. Co., Baltimore, MD (Broderbund CD-354).  On p. 90:

Clark, Abraham

Maryland

1654

2.  John Davis.  1996.  Baltimore County, Maryland, Deed Records, Volume One: 1659-1737.  Heritage Books, Bowie, MD.

p. 002	20 Oct 1661, Walter Dickenson to Abraham Clarke, 450 acres.  Signed Walter Dickenson.  Wit: Howell Powell and Thomas (x) Powell.
	2 Mar 1662, John Colleld to Abraham Clarke, 200 acres.  Signed John Colleld. Wit: Samuel Colleld and Thomas (x) Muntross.
p. 003	2 Mar 1662, John Collett to Abraham Clarke, 200 acres.  Signed John Collett.  Wit: Samuel Collett and Thomas (x) Muntross.
	7 Mar 1662, Abraham Clarke to Thomas Muntross, 200 acres.  Signed Abraham Clarke. Wit: Edward Forster and Joseph (x) Forster.
	13 Mar 1664, Thomas Muntross to John Robinson, 200 acres. Signed Thomas (x) Muntross. Wit: Abraham Clarke and Joseph Chiefsell.
p. 065	9 Feb 1679, Walter Dickenson, of Talbot Co., Maryland, to Charles Gorsuch, of same, 150 acres ...Bear creek...adjoining land Edward Loyd sold to Abraham Clark...and a tract patented by Thomas Thomas and William Battent. Signed Walter Dickenson. Wit: John Smith and Thomas Camm.
p. 066	14 Aug 1666, Lancelott Sockwell, of Rappahanock, Virginia, to Richard Ball, of Patapsco, Baltimore Co., Maryland, 300 acres...At a court held by Abraham Clark, the attorney of Lancelott Sockwell, of Rappahanock, Virginia, this Bill of Sale from Sockwell unto Mr. Richard Ball, of Patapsco, Baltimore Co., Maryland, whereas Thomas Humpheryes, late of Rappahanock, Virginia, in his will in Lancaster, Virginia, did devise to Lancelott Sockwell and John Duke a tract of 300 acres on Patapsco River, Baltimore Co., Maryland.  Signed Lancelott (x) Sockwell. Wit: William Ball and Richard Lawrence.
p. 199	4 Aug 1703, James Todd, planter, of Baltimore Co., Maryland, to Richard Fowler, 7500 pounds of tobacco, 400 acres...south side of Back River... line of Abraham Clark, Martin and Thomas Guind, Thomas and William Basfrind, Robert Harwood, Hallaway and Thomas Sparrow.  Signed James Todd. Wit: John Oldton and William Talbot.

3.  Robert W. Barnes.  1989.  Baltimore County Families, 1659-1759.  Genealogical Publ. Co., Baltimore, MD (Broderbund CD-195):

p. 114	CLARK, ABRAHAM, transp. to Md. c. 1654 or 1658/9, was in Balto. Co. by March 1662/3 when he assigned 200 a. called Nashes Creek (that he had from John Collett) to Thomas Muntross; later [actually, earlier] Walter Dickenson conv. him 450 a. Spring Neck; d. by 7 Dec. 1676 when admin. bond was posted by Miles Gibson with Thomas Long and John Arding; est. inv. on 11 Dec. 1676 by Arding and John Boring, and val. at 26,714 lbs. tob.; est. admin. in 1686 by Miles Gibson who stated that Clark's w. Sarah had also died; had iss.: MARY, m. by 11 June 1694 William Hollis; ELIZABETH, m. by Sept. 1684 William Wilkinson...
p. 334	HOLLIS, WILLIAM (2),... in 1690 William and Mary Conv. 100 a. Broad Neck to William Pritchett; on 11 June 1694 Hollis and w. conv. Landisell to William Wilkinson...
p. 388	[KINSEY, HUGH] ... w. Margaret... had iss... SARA, transp. in 1662, m. by 1667 (Abraham) Clark...
p. 691	...William [Wilkinson] was twice m.; 1st. by Sept. 1694 to Elizabeth, heir of Abraham and Sarah Clark...
Barnes certainly makes a lot of typos with his dates.  He made another one in the entry for Nicholas CORBIN.  I'm going to go with 1676 (two out of three) for the death date of Abraham (and the "death by" date of Sarah).  Mary was obviously married to William by 1690, not 1694, so she must have been born bef. 1675.  I certainly would like to know the basis of the "married by" date for Elizabeth and which one is correct.  Anybody know?

4.  Tree online at www.wikitree.com (well documented).