Langevich, H. Letter, To: Sister Olya From: Mother Helena Langevich, [n.d.].
Chicago-viite (17. p.)Langevich, Helena. Letter, To: Sister Olya From: Mother Helena Langevich, [n.d.].
MLA-viite (8. p.)Langevich, Helena. Letter, To: Sister Olya From: Mother Helena Langevich, [n.d.].
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