I read the article The Debate About Cross-Training: Cons which talks about how there has been a lot of research that has come out on Cross-training but there is still no clear answer to whether it is good or bad for your performance in your main sport. The author references a study conducted by The University of Texas, which is a credible source, that says that cross-training can be beneficial if the activities are specific compared to random and accessible. They also discuss the idea that resistance training is better than crosstraining.
