Apollodorus Library 3.10.7:
But Zeus in the form of a swan consorted with Leda, and on the same night Tyndareus cohabited with her; and she bore Pollux and Helen to Zeus, and Castor and Clytaemnestra to Tyndareus. But some say that Helen was a daughter of Nemesis and Zeus; for that she, flying from the arms of Zeus, changed herself into a goose, but Zeus in his turn took the likeness of a swan and so enjoyed her; and as the fruit of their loves she laid an egg, and a certain shepherd found it in the groves and brought and gave it to Leda; and she put it in a chest and kept it; and when Helen was hatched in due time, Leda brought her up as her own daughter.And when she grew into a lovely woman, Theseus carried her off and brought her to Aphidnae. But when Theseus was in Hades, Pollux and Castor marched against Aphidnae, took the city, got possession of Helen, and led Aethra, the mother of Theseus, away captive (original Greek).
Hyginus Fabulae 79:
Theseus, son of Aegeus and Aethra, daughter of Pittheus, along with Pirithous, son of Ixion, carried off the maiden Helen, daughter of Tyndareus and Leda, from the shrine of Diana while she was sacrificing, and took her to Athens, to a district of the Attic region. When Jove saw that they had such audacity as to expose themselves to danger, he bade them in a dream both go and ask Pluto on Pirithous’ part for Proserpine in marriage. When they had descended to the Land of the Dead through the peninsula Taenarus, and had informed Pluto why they had come, they were stretched out and tortured for a long time by the Furies. When Hercules came to lead out the three-headed dog, they begged his promise of protection. He obtained the favour from Pluto, and brought them out unharmed. Castor and Pollux, Helen’s brothers, fought for her sake, and took Aethra, Theseus’ mother, and Phisadie, Pirithous’ sister, and gave them in servitude to their sister (original Latin).
Hyginus Fabulae 92:
Jove is said to have invited to the wedding of Peleus and Thetis all the gods except Eris, or Discordia. When she came later and was not admitted to the banquet, she threw an apple through the door, saying that the fairest should take it. Juno, Venus, and Minerva claimed the beauty prize for themselves. A huge argument broke out among them. Jupiter ordered Mercury to take them to Mt Ida to Paris Alexander, and bid him judge. Juno promised him, if he should judge in her favour, that he would rule over all the lands and be pre-eminent wealth. Minerva promised that if she should come out victorious, he would be bravest of mortals and skilled in every craft. Venus, however, promised to give him in marriage Helen, daughter of Tyndareus, most beautiful of all women. Paris preferred the last give to the former ones, and judges Venus the most lovely. On account of this, Juno and Minerva were hostile to the Trojans. Alexander, at the prompting of Venus, took Helen from his host Menelaus form Lacedaemon to Troy, and married her. She took with her two handmaids, Aethra and Thisiadie, captives, but once queens, whom Castor and Pollux had assigned to her (original Latin).
Throne of Apollo at Amyklai (known through Pausanias’ description and modern reconstructions)
Pausanias Description of Greece 3.18.15:
Underneath the throne [at Amyklai], … Peirithous and Theseus have seized Helen (original Greek).
Reconstruction of whole throne by A. Furtwängler, from J.G. Frazer, Pausanias’s Description of Greece, vol. III, Commentary (2nd ed. 1913), p. 352
Chest of Kypselos from temple of Hera at Olympia (known through Pausanias’ description and modern reconstructions)
 On the chest are also the Dioscuri, one of them a beardless youth, and between them is Helen.  Aethra, the daughter of Pittheus, lies thrown to the ground under the feet at Helen. She is clothed in black, and the inscription upon the group is an hexameter line with the addition of a single word:“The sons of Tyndareus are carrying off Helen, and are dragging Aethra from Athens” (original Greek).
Detail with rescue of Helen by Dioskouroi, from reconstruction of chest of Kypselos by W. von Massow, “Die Kypseloslade,” Mitteilungen des Deutschen Archäologischen Instituts, Athenische Abteilung vol. 41 (1916), 1 ff., pl. 10.
Paris, Louvre CA 617: Protocorinthian aryballos with Helen and Dioskouroi
Drawings from L. Couve, “Un lécythe inédit du Musée du Louvre,” Revue archéologique, 3rd series vol. 32 (1898) 213 ff.
Olympia, Archaeological Museum M 397: bronze cuirass with Helen and Dioskouroi
Munich, Antikensammlungen 2309: Attic red-figure amphora with Theseus and Helen
iconiclimc (front side of amphora)
iconiclimc (detail of front side)
Edited by Aaron J. Ivey, Graduate Teaching Assistant, Department of Classics, University of Georgia, June 2016; and by Frances Van Keuren, Prof. Emerita, Lamar Dodd School of Art, Univ. of Georgia, July 2016.