Malka Mysels knows something about some branches of the Citron family. There are also some Citron families from Volhynia Gubernia, Ukraine.
Did you check Ancestry for ship manifest and naturalization / passport applications?
Would you know where Benjamin Citron is from? Whatever information you have of his family will help track down the correct branch of the Citron Family.
Meanwhile, you might find the Citron Project of some help.
http://www.geni.com/projects/Citron-Czitrom-Cytron-Citroen-Tzitron-...
I did some looking last night and found the family, but haven' t found documents for where they were from.
Also take photos of the graves if the inscriptions are in Hebrew because that will have parents' names. We can read them for you. Find a Grave may have them or you can ask a local resident to take a photo for you if the entry does not have one.
Another clue is whether they were buried in a Landsmen section of the cemetery or whether they associated in business with others from the same area. That was true for my relatives. They came together with others who were related by blood or marriage and stuck together with people from the same area.