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@@ -166,9 +166,9 @@ Courses | Duration | Effort | Prerequisites | Discussion
 [Programming Languages, Part A](https://www.coursera.org/learn/programming-languages) | 5 weeks | 4-8 hours/week | Systematic Program Design ([Hear instructor](https://www.coursera.org/lecture/programming-languages/recommended-background-k1yuh)) | [chat](https://discord.gg/8BkJtXN)
 [Programming Languages, Part B](https://www.coursera.org/learn/programming-languages-part-b) | 3 weeks | 4-8 hours/week | Programming Languages, Part A | [chat](https://discord.gg/EeA7VR9)
 [Programming Languages, Part C](https://www.coursera.org/learn/programming-languages-part-c) | 3 weeks | 4-8 hours/week | Programming Languages, Part B | [chat](https://discord.gg/8EZUVbA)
-[Object-Oriented Design](https://www.coursera.org/learn/object-oriented-design) | 4 weeks | 4 hours/week | [Basic Java](https://www.youtube.com/watch?v=GoXwIVyNvX0)
-[Design Patterns](https://www.coursera.org/learn/design-patterns) | 4 weeks | 4 hours/week | Object-Oriented Design
-[Software Architecture](https://www.coursera.org/learn/software-architecture) | 4 weeks | 2-5 hours/week | Design Patterns
+[Object-Oriented Design](https://www.coursera.org/learn/object-oriented-design) | 4 weeks | 4 hours/week | [Basic Java](https://www.youtube.com/watch?v=GoXwIVyNvX0) | [chat](https://discord.com/channels/744385009028431943/891411727294562314)
+[Design Patterns](https://www.coursera.org/learn/design-patterns) | 4 weeks | 4 hours/week | Object-Oriented Design | [chat](https://discord.com/channels/744385009028431943/891412022120579103)
+[Software Architecture](https://www.coursera.org/learn/software-architecture) | 4 weeks | 2-5 hours/week | Design Patterns | [chat](https://discord.com/channels/744385009028431943/891412169638432788)
 
 ### Core math
 Discrete math (Math for CS) is a prerequisite and closely related to the study of algorithms and data structures. Calculus both prepares students for discrete math and helps students develop mathematical maturity.