President Abraham Lincoln has been immortalized in thousands of ways.

Take a look on the Internet to discover music books, funeral tickets, posters, newspapers and other items that in some way reference the 16th President of the United States of America.

Scholars have combined to write thousands of books on Lincoln, and even Irving Berlin wrote a song about him that was sung by Bing Crosby in the film “Holiday Inn.”

“The country’s going to the dogs, they shouted loud and long. Then from a cabin made out of logs, the right man came along,” Berlin wrote.

Monday is President’s Day, a time to reflect on Abraham Lincoln and what he did for our country.

Few people will argue Lincoln’s greatness, but I was curious to know what historians specifically think made him great, so I made a few calls.

“For one thing, his humanity, his humaneness and his concern for others,” said William Harris, professor emeritus at North Carolina State University and the author of 10 books, including three on Lincoln. “He hated to see anything hurt or killed, which was ironic … because he presided over a very destructive Civil War.”

Harris described Lincoln as well-read, very intelligent and a skilled politician who was an honest and virtuous person and succeeded without caving into any interest except maybe his political party.

And not only did he lead the country through the Civil War, he was a key component in the abolishment of slavery.

“Lincoln was the only leader around that could have done it,” Harris said. “Lincoln’s leadership was critical.”

So, Mr. Harris, was Lincoln the greatest U.S. president of all time?

“Oh certainly yes,” he said. “I would classify him as No. 1 and George Washington as No. 2 … for his leadership in the Revolution and Franklin Roosevelt No. 3 for his leadership in Word War II and the depression.”

Harris added that as a former Whig who later was a pioneer of the Republican Party, Lincoln preferred to have Congress take the lead on things and then he would sign it if he felt it was right. Harris said that’s probably how Lincoln would have handled the current economic crisis if he was in office today.

“He was highly intelligent, and his judgments were good,” Harris said.

Harris is not alone in his fascination of Lincoln.

Ken Kercheval, a Los Angeles actor who is most known for his role as Cliff Barnes on the television show “Dallas,” is a long-time collector of Lincoln memorabilia.

Kercheval has sold some of his collection over the years, but said that some of the prized items he still owns include one of Lincoln’s pewter goblets and an inkwell base the president used to sign the Emancipation Proclamation.

Fans of Kercheval, 73, may be glad to know he’s still acting and even went to an audition for a movie role this past week. He also grew up in the Midwest, in Clinton, Ind., and said he’s been an avid collector of American antiques since he was 15.

“The Midwest has good antique hunting,” he said. “Here in California, there’s nothing.”

Kercheval said he didn’t think there is one president comparable to Abraham Lincoln and said he once went to the Lincoln Memorial, read the Gettysburg Address and cried.

“There is not one word in that that is superfluous or that could be changed and that would give it any deeper content,” he said.

And that’s only part of what made Lincoln great.