In the Quran, sura 4:157 says "They declared 'We have put to death the Messiah, Jesus, the son of Mary, the apostle of God'. They did not kill him, nor did they crucify him, but they had only his likeness."

The majority of Muslims believe that a substitute actually was crucified in Jesus' place. Some like Shabir Ally say that Jesus was put on the cross but did not die. (Note: This is commonly referred to as the 'swoon theory' which was shown to be false in the early 1800s, see David Strauss 'Life of Jesus')

Now the 4 gospels are very clear that Jesus was crucified and died on a cross, so I will not go into more detail on the biblical account here. Are there sources besides the bible that support the crucifixion and death of Jesus?

The Jewish Talmud, b. Sanhedrin 43a: On the eve of the Passover Yeshu [Jesus] was hanged [or crucified]. ... Since nothing was brought forward in his favor he was hanged on the eve of the Passover.

Cornelius Tacitus (a Roman historian) in his Annals, xv. 44: Christus ... was executed at the hands of the procurator Pontious Pilate.

Lucian of Samosata (a Roman historian): (Christ was) the man who was crucified in Palestine

These are Jewish and Roman sources from the 1st and 2nd century who were not Christian!

Besides the gospels, 1 Corinthians 15 contains a creed which is older than the gospels, some estimate that the creed dates to just 3 years after the crucifixion.

1 Corinthians 15:3-4 says "For I delivered to you as of first importance what I also received, that Christ died for our sins according to the Scriptures, and that He was buried, and that He was raised on the third day according to the Scriptures"

In light of the historical facts, Jesus died on the cross!