Paradise Lost is one of the works that the creature reads in Chapter 15 when he is with the De Lacey family, unbeknownst to them. The three books he reads cause him to reflect deeply about his own identity and meaning in life. Note what the creature himself concludes about how he identifies with Adam and where the similarities end:
Like Adam, I was apparently united by no link to any other being in existence; but his state was far different from mine in every other respect. He had come forth from the hands of God a perfect creature, happy and prosperous, gaurded by the especial care of his Creator; he was allowed toconverse with, and acquire knowledge from, beings of a superio nature: but I was wretched, helpless, and alone.
In fact, the creature begins to identify more with the character of Satan, as he is filled jealousy when he looks upon the De Laceys. This text then is used to highlight the way in which Frankenstein has played God by creating the creature, yet has not followed through with his responsibilities to his creation. God cared for, instructed and protected Adam, whereas Frankenstein ran away from his responsibilities and set the creature on the path to hatred and animosity.
I'm not 100% sure about 'Volney's Ruins of Empire' and 'Goethe's Sorrows of Weter', however the connection between 'Frankenstein' and 'Paradise Lost' is as follows:
The monster's narrative parallels the story of Eve and her degraded double sin, Walton and Frankenstein can both be described as 'fallen angels', the description of Victor and Elizabeth's childhood is Miltonic (Garden of Eden), the monster's 'Edenic phase' is a fiercely subversive parody of Adam- his childhood is ignorant and isolated rather than insulated and innocent; his attempts at speech parody and subvert Adam's; and the monster's anxiety and confusion are a dark version of Adam's wondering bliss.
Hopefully this helps you! Sorry I didn't know the other two... :)))