Sources

1) Source: Ottonian Germany: The Chronicon of Thietmar of Merseburg "After this, the good mother gave birth to a son... She named him Boleslav, after her brother". Reference: Book 4, Chapter 56 (Data from secondary evidence)
2) Source: Ottonian Germany: The Chronicon of Thietmar of Merseburg "Yet, with fox-like cunning, his son Boleslav unified it once more in the hands of one ruler". Reference: Book 4, Chapter 58 (Data from secondary evidence)
3) Source: Ottonian Germany: The Chronicon of Thietmar of Merseburg "But on 25 May, in the year of the Incarnation 992... the aforementioned duke, now old and feverish, went from this place of exile to his homeland". Reference: Book 4, Chapter 58 (Data from secondary evidence)
4) Source: Cosmas of Prague, The Chronicle of the Czechs "In the year of the Lord’s incarnation 977. Doubravka died. She was very shameless for when in her advanced age she married the duke of Poland"
5) Source: Ottonian Germany: The Chronicon of Thietmar of Merseburg "Wishing to acquire a wife for his son from the emperor at Constantinople... this ruler sent across the sea to our emperor, not the desired maiden, but rather his niece, Theophanu". Reference: Book 2, Chapter 15 (Data from secondary evidence)
6) Source: Ottonian Germany: The Chronicon of Thietmar of Merseburg "He married the daughter of Margrave Rikdag, but later sent her away and took a Hungarian woman as his wife. She bore him a son, named Bezprym, but he also sent her away. His third wife was Emnilde, a daughter of the venerable lord, Dobromir... Shebore two sons, Miesco and another one whom the father named after his beloved lord. She also produced three daughters of whom one was an abbess, the second married Count Herman, and the third the son of King Vladimir". Reference: Book 4, Chapter 58 (Data from secondary evidence)