Tacitus: During the consulship of Paulus Fabius and Lucius Vitellius, the bird called the phoenix, after a long succession of ages, appeared in Egypt and furnished the most learned men of that country and of Greece with abundant matter for the discussion of the marvelous phenomenon. It is my wish to make known all on which they agree with several things, questionable enough indeed, but not too absurd to be noticed. That it is a creature sacred to the sun, differing from all other birds in its beak and in the tints of its plumage, is held unanimously by those who have described its nature. As to the number of years it lives, there are various accounts. The general tradition says five hundred years. Some maintain that it is seen at intervals of fourteen hundred and sixty-one years, and that the former birds flew into the city called Heliopolis successively in the reigns of Sesostris, Amasis, and Ptolemy, the third king of the Macedonian dynasty, with a multitude of companion birds marvelling at the novelty of the appearance. But all antiquity is of course obscure.
Claudian, The Phoenix He knows his time is out! and doth provide New principles of life; herbs he brings dried From the hot hills, and with rich spices frames A Pile shall burn, and Hatch him with his flames. On this the weakling sits; salutes the Sun With pleasant noise, and prays and begs for some Of his own fire, that quickly may restore The youth and vigor, which he had before. Whom soon as Phoebus * spies, stopping his rays He makes a stand, and thus allays his pains...... He shakes his locks, and from his golden head, Shoots on bright beam, which smites with vital fire The willing bird; to burn is his desire. That he may live again; he's proud in death, And goes in haste to gain a better breath. The spice heap fired with celestial rays Doth burn the aged Phoenix, when straight stays The Chariot of the amazed Moon; the pole Resists the wheeling, swift Orbs, and the whole Fabric of Nature at a stand remains. Till the old bird anew, young begins again.
Hesiod, Precepts of Chiron Fragment 3 (from Plutarch de Orac. defectu 2.415C) (trans. Evelyn-White) (Greek epic C8th or C7th B.C.) : "A chattering crow lives out nine generations of aged men, but a stag's life is four times a crow's and a raven's life makes three stags old, while the Phoinix outlives nine raves, but we, the rich-haired Nymphai (Nymphs), daughters of Zeus the aigis-holder, outlive ten Phoinixes (Phoenixes)."
Herodotus, Histories 2. 73 (trans. Godley) (Greek historian C5th B.C.) : "There is another sacred bird, too, whose name is Phoinix (Phoenix). I myself have never seen it, only pictures of it; for the bird seldom comes into Aigyptos (Egypt): once in five hundred years, as the people of Heliopolis say. It is said that the Phoinix comes when his father dies. If the picture truly shows his size and appearance, his plumage is partly golden and partly red. He is most like an eagle in shape and size. What they say this bird manages to do is incredible to me. Flying from Arabia to the temple of the Helios (the Sun), they say, he conveys his father encased in myrrh and buries him at the temple of Helios (the Sun) [i.e. in the temple of the Egyptian god Ra]. This is how he conveys him: he first molds an egg of myrrh as heavy as he can carry, then tries lifting it, and when he has tried it, he then hollows out the egg and puts his father into it, and plasters over with more myrrh the hollow of the egg into which he has put his father, which is the same in weight with his father lying in it, and he conveys him encased to the temple of the Sun in Aigyptos (Egypt). This is what they say this bird does."
Aelian, On Animals 6. 58 (trans. Scholfield) (Greek natural history C2nd A.D.) : "The Phoinix (Phoenix) knows how to reckon five hundred years without the aid of arithmetic, for it is a pupil of all-wise nature, so that it has no need of fingers or anything else to aid it in the understanding of numbers. The purpose of this knowledge and the need for it are matters of common report. But hardly a soul among the Aigyptoi (Egyptians) knows when the five-hundred-year period is completed; only a very few know, and they belong to the priestly order. But in fact the priests have difficulty in agreeing on these points, and banter one another and maintain that it is not now but at some date later than when it was due that the divine bird will arrive. Meantime while they are vainly squabbling, the bird miraculously guesses the period by signs and appears. And the priests are obliged to give way and confess that thy devote their time ‘to putting the sun to rest with their talk’; but they do not know as much as birds. But, in God's name, is it not wise to know where Aigyptos (Egypt) is situated, where Heliopolis whither the bird is destined to come, and where it must bury its father and in what kind of coffin?"
Philostratus, Life of Apollonius of Tyana 3. 49 (trans. Conybeare) (Greek biography C1st to C2nd A.D.) : "‘And the Phoinix (Phoenix),’ he [the Indian sage Iarkhas, C1st A.D.] said, ‘is the bird which visits Aigyptos (Egypt) every five hundred years, but the rest of that time it flies about in India; and it is unique in that it gives out rays of sunlight and shines with gold, in size and appearance like an eagle; and it sits upon the nest; which is made by it at the springs of the Nile out of spices. The story of the Aigyptoi (Egyptians) about it, that it comes to Aigyptos, is testified to by the Indians also, but the latter add this touch to the story, that the Phoinix which is being consumed in its nest sings funeral strains for itself. And this is also done by the swans according to the account of those who have the wit to hear them.’"
Ovid, Metamorphoses 15. 385 ff (trans. Melville) (Roman epic C1st B.C. to C1st A.D.) : "These creatures [other races of birds] all derive their first beginnings from others of their kind. But one alone, a bird, renews and re-begets itself--the Phoenix of Assyria, which feeds not upon seeds or verdure but the oils of balsam and the tears of frankincense. This bird, when five long centuries of life have passed, with claws and beak unsullied, builds a nest high on a lofty swaying palm; and lines the nest with cassia and spikenard and golden myrrh and shreds of cinnamon, and settled there at ease and, so embowered in spicy perfumes, ends his life's long span. Then from his father's body is reborn a little Phoenix, so they say, to live the same long years. When time has built his strength with power to raise the weight, he lifts the nest--the nest his cradle and his father's tomb--as love and duty prompt, from that tall palm and carries it across the sky to reach the Sun's great city [i.e. Heliopolis in Egypt], and before the doors of the Sun's holy temple lays it down."
Statius, Silvae 3. 2. 101 (trans. Mozley) (Roman poet C1st A.D.) : "Altars [in Egypt] the long-lived Phoenix prepares for his own death."
some Greek sources appear courtesy of Theoi.com