Somerset v Stewart (English Wikipedia)

"Slavery in England". Anti-Slavery Society. Retrieved 18 September 2015. In 1824 in Forbes v Cochrane (1824) 3 Dow & Ry KB 679 at 742, 2 B & C 448 at 463, 107 ER 450 at 456, 2 State Trials NS 147, Holroyd J held that where a person gets out of the territory where it [slavery] prevails and out of the power of his master and gets under the protection of another power, without any wrongful act done by the party giving that protection, the right of the master, which is founded on the municipal law of the particular place only, does not continue.

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van Cleve, George (2006). ""Somerset's Case" and Its Antecedents in Imperial Perspective". Law and History Review. 24 (3): 601–645. doi:10.1017/S073824800000081X. ISSN 0738-2480. JSTOR 27641404. S2CID 145793676.
Oldham, James (1988). "New Light on Mansfield and Slavery". Journal of British Studies. 27 (1): 45–68. doi:10.1086/385904. JSTOR 175399. S2CID 159665835.
Nadelhaft, Jerome (1966). "The Somersett Case and Slavery: Myth, Reality, and Repercussions". The Journal of Negro History. 51 (3): 193–208. doi:10.2307/2716061. JSTOR 2716061. S2CID 150260460.
Zilversmit, Arthur (October 1968). "Quok Walker, Mumbet, and the Abolition of Slavery in Massachusetts". The William and Mary Quarterly. Third. 25 (44). Omohundro Institute of Early American History and Culture: 614–624. doi:10.2307/1916801. JSTOR 1916801.

Letter to the London General Evening Post of 21–23 June 1772, headed by the following. "To the Editor of the general evening post. SIR, The following is as correctly my Lord M——d's Speech on the Negro Cause, as my memory, assisted by some notes, could make it: it begins after the stating of the return. Your's, & c. A CONSTANT READER." The letter is somewhat at variance with other sources reporting on the words of the Mansfield Decision (including the citation in the previous section of this article). Such inconsistencies may be related to the enthusiasm which abolitionists propagated the decision, and the spin which they sought to put on it in relation to their campaign. See, "Slavery in England and the Law" Archived 2 January 2007 at the Wayback Machine, History Cooperative

van Cleve, George (2006). ""Somerset's Case" and Its Antecedents in Imperial Perspective". Law and History Review. 24 (3): 601–645. doi:10.1017/S073824800000081X. ISSN 0738-2480. JSTOR 27641404. S2CID 145793676.
Oldham, James (1988). "New Light on Mansfield and Slavery". Journal of British Studies. 27 (1): 45–68. doi:10.1086/385904. JSTOR 175399. S2CID 159665835.
Nadelhaft, Jerome (1966). "The Somersett Case and Slavery: Myth, Reality, and Repercussions". The Journal of Negro History. 51 (3): 193–208. doi:10.2307/2716061. JSTOR 2716061. S2CID 150260460.
Justin Buckley Dyer, "After the Revolution: Somerset and the Antislavery Tradition in Anglo-American Constitutional Development"], The Journal of Politics Vol. 71, No. 4 (Oct. 2009), pp. 1422–1434, Published by: Cambridge University Press, JSTOR 20622367
Wiecek, William M. JSTOR 1599128 "Somerset: Lord Mansfield and the Legitimacy of Slavery in the Anglo-American World", University of Chicago Law Review, Vol. 42, No. 1 (Autumn 1974), pp. 86–146
Zilversmit, Arthur (October 1968). "Quok Walker, Mumbet, and the Abolition of Slavery in Massachusetts". The William and Mary Quarterly. Third. 25 (44). Omohundro Institute of Early American History and Culture: 614–624. doi:10.2307/1916801. JSTOR 1916801.

van Cleve, George (2006). ""Somerset's Case" and Its Antecedents in Imperial Perspective". Law and History Review. 24 (3): 601–645. doi:10.1017/S073824800000081X. ISSN 0738-2480. JSTOR 27641404. S2CID 145793676.
Oldham, James (1988). "New Light on Mansfield and Slavery". Journal of British Studies. 27 (1): 45–68. doi:10.1086/385904. JSTOR 175399. S2CID 159665835.
Nadelhaft, Jerome (1966). "The Somersett Case and Slavery: Myth, Reality, and Repercussions". The Journal of Negro History. 51 (3): 193–208. doi:10.2307/2716061. JSTOR 2716061. S2CID 150260460.

Harper, Douglass. "Slavery in Massachusetts". Slavery in the North. Retrieved 10 June 2007.
Harper, Douglass. "Emancipation in Massachusetts", Slavery in the North. Retrieved 22 May 2010

"Constitution of Vermont (1777)". Chapter I, Article I: State of Vermont. 1777. Archived from the original on 25 July 2012. Retrieved 12 February 2014.

Letter to the London General Evening Post of 21–23 June 1772, headed by the following. "To the Editor of the general evening post. SIR, The following is as correctly my Lord M——d's Speech on the Negro Cause, as my memory, assisted by some notes, could make it: it begins after the stating of the return. Your's, & c. A CONSTANT READER." The letter is somewhat at variance with other sources reporting on the words of the Mansfield Decision (including the citation in the previous section of this article). Such inconsistencies may be related to the enthusiasm which abolitionists propagated the decision, and the spin which they sought to put on it in relation to their campaign. See, "Slavery in England and the Law" Archived 2 January 2007 at the Wayback Machine, History Cooperative
"Constitution of Vermont (1777)". Chapter I, Article I: State of Vermont. 1777. Archived from the original on 25 July 2012. Retrieved 12 February 2014.