what is minimum recomended cage size?
the minimum cage requirement is 4ft tall by 2 ft deep by 3 ft long but bigger is always better

can they be kept outside during the warm months?
i personally dont like keeping them or any reptile outside because of the chance of an animal or toxic insect getting in and not always will u be able to get a proper temp for them

What is the best diet for these guys?
they are mostly insectivores but occasionally will have a small mammal such as a pinkie mouse and some (including mine) will eat greens and fruits

do they require uvb lighting?
yes they require a full spectrum UVB (i swear by megaray MVB bulbs and reptisun 10.0's)

what is a good websie or good book to get more info on the guys?
honestly im not sure of any sites other than looking on forums and most books are very outdated especially on frilled dragons
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1.0.0 Frilled Dragon - Frank
0.0.1 Rhinoceros Iguana - Mo
2.1.1 Bearded Dragons - Magellan, Galileo, Lizzy, & Machiavelli