TO FURTHER VERIFY the dominance these days of the international set when it comes to golf, Simon and Schuster, the book publisher in New York, has just released its two prize golf books in time for the summer golf season. One is written by Gary Player, a South African. The other is written by Greg Norman, an Australian.

"Golf Begins at 50" is Player's book."Shark Attack" is Norman's book.

Both are the same number of pages and both have the same number of helpful instructional photos, but for some reason Norman's book sells for $19.95 and Player's for $18.95.

You would think it would be the other way around, since Player's book is obviously intended for those players 50 and over who are in higher income brackets and think nothing of spending $550 every spring on a new graphite driver.

In the interest of further complicating the golf swing - it is that time of the year - herewith a few helpful excerpts from these new releases: First, from Norman's book, which is subtitled "Greg Norman's Guide to Aggressive Golf."

Now, you might be thinking, "that takes a lot of nerve. The same Greg Norman who held the third round lead going into the final round of each of the four majors in 1986 - and then lost three of them - writing a book about winning aggressively?" Norman talks about that in the book.

"Leading all four majors in one year was something no one had ever done, and it was a satisfying achievement for me," he writes. "Failing to win three out of the four was not satisfying. Nor, to be sure, was the experience at the 1987 Masters. But through those disappointments I learned that I am good enough to lead all four majors in a single year . . . and to hold or share the final-round lead in five. And if I can lead them during those final rounds, certainly I can lead them after the tournaments are over. All four of them. In the same year. Yes, I learned that I am capable of winning the Grand Slam . . . This is my goal."

Once he does that, $19.95 for a Norman book will be a bargain.

As you might guess from the title, Norman's book is not for the faint of heart. He talks about playing golf like a young Arnold Palmer. He talks about using enough club, about "going for the top of the flag," about always putting 17 inches through the hole and about trouble shots. He even has a chapter about gamesmanship wherein he reveals helpful tee box hints that can rattle your opponent - such as taking out your driver on the tee box of a tight par-four and then, after your partner has hit his driver, put it back in the bag and hit the 3-iron you planned to hit all along.

Norman talks about the need to be motivated. As an example, he recounts an experience he had at the end of the '86 season. He had won six golf tournaments in an 8-week stretch coming into the final event of the year, the Western Australian Open. He was tired of golf and even tired of winning and was well off the pace after two rounds.

He called his wife, Laura, and told her he just wasn't fired up to play. "Find me some motivation," he asked. So Laura did. She told him he had already placed first on the money-winning list in America, and with a win in Western Australia he could clinch the money-winning title for the Australian Tour as well. So get out there and win one for the lucre.

She also said - presumably - that she had her eye on this sharp little burgandy Jaguar convertible.

Norman, now properly motivated, shot 66-68 the final two rounds and won.

Player's book starts where Norman's leaves off.

Here's a man who is a mature golfer. He won 21 times on the PGA Tour - including a victory in each of the four majors. And in the past two seasons since turning 50 and joining the Senior Tour he has won seven Senior events, including the U. S. Senior Open and the PGA Senior Championship.

Player's book is heavy on philosophy, self-discipline and encouragement.

It sounds vaguely familiar - like it was written by your father.

Player, himself a living (f somewhat annoying) example of fitness of mind and body, touches on regular exercise (t least an hour a day five days a week), proper diet (wo meals a day is plenty and stay away from butter, cream, sugar, coffee, white bread, red meat and so on), concentration (tare at a light bulb for 20 minutes a day), meditation and yoga as helps to both a healthy life and a healthy game of golf.

He also touches on an over-50 golf swing he calls the Walk-Through, a swing that cuts down on the big bend popular with younger players and reduces the pressure on the lower back.

He strongly recommends metal woods for over-50 players, surlyn balls and heel-toe weighted putters . . . and if it isn't upbeat leave it alone.

"I play with people who enjoy their golf," he writes. "I stay away from grouches or anyone who lets the game make them miserable, and so should you."

Such advice could cut down on the overcrowdedness problems at local golf courses.

If you do as Player says you should do, he says you'll be a walking, talking example of that old Scottish saying: "Lang may his lum reek." Or, "Long may his chimney smoke."

"I'd rather be 70 years young than 40 years old," he writes.

If you can handle more advice, buy the books.