Name is not a pseudonym 

The man changed his name to the current name which is Mark A. Gabriel. So, Mark A. Gabriel is the new real name for this man.

This is from the introduction page of "Islam and Terrorism";

The NAME YOU see on the cover of this book is not the Muslim name that was given to me by my parents in Egypt. However, I would like to say that I have no desire to deceive Muslims, Christians or anyone else about my name in order to benefit my self. Rather, I have chosen my name for the following reasons.

Reason #1
After I left Egypt, I went to South Africa and was discipled in Christ there. When I began ministering to Muslims in South Africa, I became very well known by my Muslim name. For four years radical Muslims pursued me diligently. I had to hide all the time and change my residency from one city to another almost on a monthly basis. When I wrote my first book in South Africa, my pastor and I discussed whether I should put my name on it. We decided to change my name for security reasons.

Reason #2
I was not comfortable living my Christianity by a Muslim name. I felt my Muslim name was part of my old man. When a person called me by that  name, it reminded me of my old life. I want to live by a Christian name.

Choice of name
I chose the first name of Mark because Mark was a writer of the Gospels. Mark was also the first Christian who went to Egypt with the Good News. When Jesus sent the seventy out from Jerusalem, Mark brought the gospel to the city of Alexandria in Egypt. I chose the last name of Gabriel because Gabriel was the angel who brought the good news of the coming of the Messiah to the virgin Mary. Also this was the name of the first Christian person I met in South Africa who took me into his home and invited me to his church.

This proves that this man is not a hoax, and is not more than one author.  | Talk