History of the Kings of England by John Rous is in Late Medieval Books.
And thus the new king, torn from his most faithful ones, was received with kisses and embraces, like an innocent lamb that fell into the hands of wolves. His principal guide in morals, the diligent teacher of God's will, Master Johannes Alkok, Bishop of Worcester, was also removed, though not burdened by the harshness of imprisonment. What more? The new king, led to London, was received honourably by the mayor and the citizens, as was fitting. Under his name, the laws of the kingdom were observed with the usual reverence at Westminster and throughout the entire realm."
Et sic novus rex à fidelissimis suis avulsus cum osculis & amplexibus receptus ut innocens agnus in manus luporum cecidit. Ejus etiam præcipuus ad mores diligens ad Dei placitum tunc informator magister Johannes Alkok episcopus Wigornensis ut ceteri amotus est, non tamen carcerali rigore gravatus. Quid plura? Novus rex Lundoniæ ductus, à majore & concivibus honorifice, ut decuit, est receptus. Sub ejus nomine jura regni apud Westmonasterium & per totum regnum sunt modo sblito observata.
[July 1483] He [King Richard III of England [aged 30]] received his lord King Edward V blandly, with embraces and kisses, and within about three months or a little more, he killed him along with his brother, and poisoned Queen Anne, his wife, the daughter of the Earl of Warwick.
Dominum suum regem Edwardum quintum blandiendo cum amplexibus & osculis recepit, & infra circiter tres menses vel parum ultra cum fratre suo interfecit, & dominam Annam reginam suam filiam comitis Watrwici intoxicavit.
He imprisoned his own mother, the venerable Anne, countess and the lady and most rightful heiress of that noble lordship, during her lifetime, even though she had fled to him for refuge. And what was most detestable in the sight of God and of all the English, indeed of all nations to whose knowledge it came, was that he caused that most holy man, King Henry VI, to be killed by others, or, as many believed, even by his own hand. And because there was a certain prophecy that after E., that is, after Edward IV, G. would reign, under this ambiguity George, duke of Clarence, the middle brother of the two kings Edward and Richard, was for this reason killed.
Matrem suam Annam venerabilem comitissam, illius nobilis dominii Dominam & justissimam heredem, durante vita sua incarceravit, quæ sibi maximi causa refugii confugerat. Et quod in Dei & omnium Anglicorum, immo omnium nationum ad quorum notitiam pervenit, detestabilissimum erat, ipsum sanctissimum virum regem Henricum sextum per alios, vel multis credentibus manu poc ius propria interfecit. Et quia erat quædam prophetia, quod post E. id est, post Edwardum quartum, G. regnaret, sub hoc ambiguo Georgius dux Clarenciæ, medius amborum fratrum Edwardi & Ricardi regum, dux ob hoc Georgius peremptus est.