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Theta - Wikipedia
Theta Symbol (θ)
The /θ/ sound - YouTube
Theta Symbol in Greek Alphabet Θ θ
Theta Thoroughly: Symbolizing Thought and Theory
Greek alphabet - Wikipedia
Theta Symbol And Its Meaning – Theta Letter/Sign In
Theta - Simple English Wikipedia, the free encyclopedia
Greek letters used in mathematics, science, and engineering
θ - Wiktionary, the free dictionary