Sources

1) Source: Court of Chancery: Six Clerks Office: Early Proceedings, Richard II to Philip and Mary "Plaintiffs: Richard Beauchamp, esq., son of John lord Beauchamp, and Elizabeth his wife, daughter of Humphrey Stafford, knt., late of Grafton.". Reference: C 1/24/186 (Data from direct source)
2) Source: England & Wales, Prerogative Court of Canterbury Wills, 1384-1858 Record for Johis Beanchamp. External Link
https://search.ancestry.co.uk/cgi-bin/sse.dll?db=5111&h=877503&indiv=try. Reference: The National Archives; Kew, Surrey, England; Records of the Prerogative Court of Canterbury, Series PROB 11; Class: PROB 11; Piece: 7
3) Source: Varied - Secondary Source for Medieval Genealogy "...I identified Margaret Ferrers, wife of John Beauchamp, as the daughter of Edmund Ferrers, 6th Lord Ferrers, of Chartley, co. Stafford, in the book, Plantagenet Ancestry, 2nd edition, by David Faris, pp. 138, 216. This identification was made based on the following information:1. Margaret (Ferrers) Beauchamp named her brother, Richard Ferrers, in her PCC will proved in 1488. For an abstract of Lady Margaret's will, see the book, Testamenta Vetusta.2. Reviewing the high born Ferrers families of this period, I determined that Edmund Ferrers, 6th Lord Ferrers, of Chartley (died 1435), had a younger son named Richard who would fit chronologically to be Margaret's brother.3. I went through the published Patent and Close rolls of this period. I found that Margaret's husband, John Beauchamp, served as a feoffee in 1442 for William Ferrers, Knt., of Chartley, eldest son of Edmund Ferrers. This would be what what one would expect to find if Margaret was Edmund's daughter, as feoffees were often close relatives. Conversely, if John Beauchamp had no connection with the Chartley family, it would be difficult to explain his appearance as a feoffee for the Ferrers family of Chartley.4. Margaret Ferrers was evidently named for Edmund Ferrers' mother, Margaret (Despencer) Ferrers...". External Link
https://groups.google.com/g/soc.genealogy.medieval/c/l5gehH_lLd0. Reference: Post by Douglas Richardson dated 16 July 2001 to soc.genealogy.medieval (Questionable reliability of evidence)
4) Source: Victoria County History. Reference: Madresfield; A History of the County of Worcester: volume 4 (Data from secondary evidence)
5) Source: Court of Chancery: Six Clerks Office: Early Proceedings, Richard II to Philip and Mary "Short title: Clarke v Lygon.Plaintiffs: William Clarke.Defendants: Richard Lygon, knight, and George Lygon, gentleman, sons of Anne, late the wife of Richard Lygon, esquire, and a daughter and heir of Richard Beauchamp, lord Beauchamp.Subject: Annuity in Kemerton of the grant of the said Anne. Gloucestershire1532-1538". Reference: C 1/769/32 (Data from direct source)
6) Source: Chancery: Inquisitions Post Mortem, Series II, and other Inquisitions, Henry VII to Charles I "Richard Beauchamp, knight, lord de Beauchamp...The said Richard Beauchamp, late lord de Beauchamp, died 16 January, 18 Henry VII...Anne wife of Richard Ligon is the other of his daughters and heirs...the said Anne is aged 30 and more"Dated: 1505. External Link
https://www.british-history.ac.uk/inquis-post-mortem/series2-vol2/pp545-574. Reference: C 142/18/40 (Data from direct source)
7) Source: The Visitation of the County of Worcester made in the year 1569. Reference: Lygon pedigree (Data from secondary evidence)