Two very different books that might interest Flyers fans are available for the holidays. One weighs about as much as the average new-born baby and is filled with exhaustive research done by Jay Greenberg. The other is a heartfelt story about the personal life of Keith Allen and how he steered the Flyers to greatness.

If you're a Flyers fan, they are must-reads, and both have revealing forewards by former club chairman and co-founder Ed Snider, who died in April.

In Greenberg's "The Philadelphia Flyers at 50," the author superbly  documents everything (and I mean EVERYHING) that has happed in the franchise's history, and it includes lots of behind-the-scenes revelations.

The other book is "Keith the Thief," lovingly written by Blake Allen, whose father, Keith, a Hockey Hall of Famer, was one of the most influential people in the franchise's history.

Greenberg, in "The Philadelphia Flyers at 50," writes that one of the reasons Paul Holmgren stepped down from the general manager's job was because he sensed other GMs didn't want to deal with him after he signed restricted free-agent Shea Weber to a 14-year, $110-million offer sheet in 2012.

"It's hard to do this job if you have a bad relationship, or at least a perceived bad relationship, with any number of GMs," Holmgren told Greenberg.

Holmgren said that even though restricted free-agent offers are legal, they are "really frowned upon" and that his relationship with a lot of other general managers "changed."

Some other great tidbits: At the 2013 draft, Dallas offered the 10th overall pick for Brayden Schenn. The Flyers passed. Dallas took 6-4, 205-pound right winger Valeri Nichushkin, who scored 23 goals in 166 games with the Stars and then went back to play in Russia's KHL this season.

At that same draft, Montreal dangled Max Pacioretty and the Canadiens' 25th overall draft pick for Wayne Simmonds and the Flyers' 11th overall pick, which turned out to be Sam Morin.

The book is 594 pages and coincides with the franchise's 50th anniversary season. Fittingly, it includes the top 50 Flyers wins and the top 50 events.

It also features, in order, the top 50 Flyer heroes - Ed Snider is No. 1, Bobby Clarke is No. 2, and Allen is No. 3 - in franchise history. Some other "heroes:" Claude Giroux is No. 16, Simmonds is No. 38, and Jake Voracek is No. 42 .

"Keith the Thief," is the author's story about how his dad influenced the franchise.

In his foreward, Snider writes that a few years after the Flyers traded enforcer Dave Schultz, "I was pushing and pushing to bring Davey back until finally Keith exploded. "You want him so goddamn badly, I'll get him for you."

Added Snider: "To me, that said, 'You're the owner but this is against my better judgment."

Snider backed down. Schultz wasn't brought back.

In the book, Snider said because of the colorful and talented teams Allen built as a GM, "The Flyers have fans everywhere, a fact reflected by how much orange you see in the stands when our team is on the road. I believe our profile in hockey is comparable to the Dallas Cowboys in football. And that started with Keith Allen. Keith didn't care about credit, only about Stanley Cups."

Blake Allen calls the book a "fly-on-the-wall perspective of Dad's life....a collection of memories of growing up in an exceptional time, and learning from an exceptional man."

He makes some interesting observations about Snider, saying he had an "almost Zen-like positive attitude" and that the owner's first wife, Myrna "exuded an almost hippie-like warmth and generosity that complemented Eddie's energy....They rejected negativity. They rejected failure," and they "expected May 19th, 1974 to happen."

That was when the Flyers won their first Stanley Cup.

Allen wrote that his dad and Snider were "so different in their approach to life that it's really amazing they co-existed successfully." His dad's outlook on life wasn't as cerebral as Snider's. "Keith's approach was more mechanical; if life was crooked, pound it straight."

Wrote Allen, whose dad was the architect of the Flyers' 1974 and 1975 Stanley Cup championships: "While Ed Snider required that each of his children read Ayn Rand's "Atlas Shrugged," Keith required that each of his children do their "goddamn homework."

Keith Allen called the Broad Street Bullies the "Gas House Gang," borrowing from the St. Louis' Cardinals' 1934 baseball team that played with lots of grit, Blake Allen wrote.

"It's ironic that Dad was inducted into the Hockey Hall of Fame builders category...because he couldn't hammer a nail, couldn't build a model airplane, couldn't fix the dryer," Allen wrote. "Keith could only build one thing: He could build hockey teams. When I was 10 years old, Dad said to me: 'Babe, we're going to get guys  who hate to lose; guys with character.' And that was Keith the Thief's blueprint for all the years that he was the Flyers' GM."

Keith Allen loved physical teams with tough players, like the 2011 Stanley Cup champion Boston Bruins, his son wrote.

"As the culture of professional hockey evolved into the modern ages, there were a few new-age ideas that veered a little too far to the left of Dad's old-time hockey values," Allen wrote. "In 2009, when the Flyers went on a 'team bonding' sailing trip in Florida, I asked whether he thought (hard-nosed) Eddie Shore would have taken his players sailing," Allen wrote.

Keith's response: "He'd have thrown us overboard!"