1.  Frederick Adams Virkus, ed.  1933.  The Compendium of American Genealogy.  Institute of American Genealogy, Chicago (repub. 1968 by Genealogical Publ. Co., Baltimore; Broderbund CD-200):

p. 2067

10-John Slaughter, said to have settled in Va. before 1620, received a land grant on Knight's Creek, Essex Co., Va., 1635; 9-Francis (1630-56) capt. of militia, justice Rappahannock, Va. m 1652, Elizabeth, dau. of Col. William Underwood;  8-Francis (1653-1718), Richmond Co., Va., m 1679, Margaret Hudson;  7-Robert (1680-1726), Essex Co., Va., m 1700, Frances Ann Jones (Lt. Col. Cadwallader 8; Richard 9)  6-Francis (1701-66), col. militia, justice, church warden, m 1729, Anne Lightfoot;

p. 2068

5-John, Culpeper Co., Va., mem. Com. Safety, m 2d, 1758, Elizabeth (b 1742), dau. Edgcombe Suggett, Richmond Co., Va. (three sons in Cont. Army) 4-John Suggett (1759-1830), soldier Am. Rev. at 16, magistrate, high sheriff, m 1779, Susanna, dau. Capt. William Brown; 3-William (1792-1866), Fredericksburg, Va., m 1813, Harriet (1796-1881), dau. Fielding Ficklen (4 above)

2.  Raleigh Travers Green.  1958.  Genealogical and Historical Notes on Culpeper County, Virginia: Embracing a Revised and Enlarged Edition of Dr. Philip Slaughter's History of St. Mark's Parish.  Southern Book Co., Baltimore, MD (online at GenealogyLibrary.com):

p. 85	JOHN SLAUGHTER (Francis, Robt.) m. Milly Coleman, dau. of Robt. Coleman, and had, 1. Robert, m. sister of Gov. Slaughter, of Ky., and had two sons Chas. and Edward, and several daughters. 2. Cadwallader, m. 1st. Miss Yancey, 2nd. Miss Hampton, and had Rich., Jno. H., Robt., Edward, Cadwallader, and several daughters. 3. and 4. Francis and Thos. K., both went to Ky. 5; John S. m. dau. of Capt. William Brown, and had thirteen children, who were: 1. Col. John Slaughter, of Culpeper, m. dau. Maj. Gabriel Long, and had four daughters, Mrs. C.C. Conner, Mrs. Gabriel Long, Mrs. George Slaughter, and Emily, died single. 2. William, m. Miss Ficklen, and had I. Franklin, m. Miss Gill, having Lawrence, Frank, Etta, and Harriet, who m. Mr. Tackett, vestryman of St. George's Church, Fredericksburg. II. Montgomery, m. Eliza Lane Slaughter, having Wm., Philip, Mary Montgomery, Fanny, Charles, and Bessie. III. J. Warren, m. Sallie Braxton.. IV. Elizabeth, m. R. Garnett. V. Sallie, m. Jno. F. Ficklen, having Kate and Harry. VI. Jennie, m. Dr. Kerfoot. VII. Matilda. VIII: Fanny. 3. Samuel, m. Allen. 4. Philip, m. 1st. Eliza, dau. of Wm. Lane, and had Eliza; m. 2nd. Mrs. Fletcher; m.3rd. Mrs. Robinson. 5. Reuben, m. Emily, dau. of R. Long, of Baltimore, having I. Albert, m. 1st. Mary Edmonia Rogers, had 1. Wm. Pendleton, m. Mollie Rea Duncan, 2. Frank;, Albert m. 2nd. Louise Cary Funston, having 1. Emily Virginia, 2. Sue Meade, 3. Jas. Albert, 4. Evelyn, 5. Homozelle, 6. Eleanor, 7. Louise Nelson. II. Frank L., m. Susan Fitzhugh Motley, of Caroline, having 1. Albert Judson, m. Virginia Jackson Daniel, 2. Gibbon Minnigerode, 3. Frank Raymond, 4. Persis Read. III. Anne Trippe, m. Dr. Boulware, of Caroline, having McCalla, who m. Ada Jackson Miller, and had 1. Jackson Darius, 2. Gideon Brown, 3 Elizabeth Trippe. IV. Maria, m. Rev. Mr. Buckner, of Caroline. 6. Thomas Jefferson, m. dau. of Capt. R. Moore, having I. Reuben, m. Miss Turner, and had 1. Lou Turner, 2. Thomas Jefferson, 3. Milton, m. Miss Wright, 4. Marcellus, 5 Anne W., 6. Herbert, 7. Anna C. II. Susan, m. Col. Coons. III. Anne, m. Lieut. Winfield, killed at Spottsylvania C. H., in 1864. 7. Albert Gallatin, Commander in the U.S. Navy, m. Miss Emily Randall, of Baltimore, having I. Josephine. II. Emily G., m. Judge Stuart, a lawyer of distinction of Baltimore, having 1. Wm. m. Miss Carter, of Fauquier, 2. Emily, m. Lieut. Macklin, U.S. Navy, 3. Kate, m. Mr. Drake, 4. Lewis. 8. James Madison, m. Miss Long, of Baltimore, and had I. Mary, m. Rev. J.G. Minnigerode.  9. Mary, m. John S. Long. of Ky.  10. Elizabeth, m. Mr. Downer, and with eleven children lived in Ky.  11. Lucy, m. 1st. Gabriel Long: 2nd. Thos. S. Long, both sons of Maj. Gabriel Long, of Culpeper.  12. Nancey, m. Reese Jury, and had I. John S., m. Miss Wolfe. II. Lewis C., m. Miss Holt, and lived in New Orleans. III. Mary, m. Edward R. Gaines, having Dr. J. M. Gaines, of Hagerstown, Md., James, surgeon in the U.S.N., Archibald, m. Freeman, Lucy, m. Crawford, Bettie and Susan. IV. a dau. m.
p. 86	John Long, Ky. V. Catherine, m. J.M. Lewis. VI. Bettie m. Rev. Mr. Huff. VII. Susan. VIII. Margaret. IX. Francis [errata sheet says "Frances"].  13. Susan, m. Roberts Menefee, and moved to Missouri.
p. 45	Following the notes from wills we give the complete marriage record of Culpeper from the year 1781 to January 1, 1825.
p. 55	MARRIAGE RECORD. [Note: The year of marriage only is given. From 1781 to 1825.]
p. 64	Reese Jury, Anne Slaughter, 1811...

3.  Messages in the Long Family Genealogy Forum (online at GenForum.com).

4.  David R. Downer.  1900.  The Downers of America, with Genealogical Record.  Self-published, Newark, NJ (online at GenealogyLibrary.com).

5.  WorldConnect (online at RootsWeb.com).