Text: A new alliance with England was sealed in the 1386 Treaty of Windsor; a year later Joao of Avis married Philippa of Lancaster, the daughter of John of Gaunt.
Entailment: A new alliance was formed with England in the 1386 Treaty of Windsor just one year before Joao of Avis married Philippa of Lancaster.
Contradiction: Joao of Avis never married Philippa of Lancaster, the daughter of John of Gaunt.