The Aliens :

The Aliens by Murray Leinster is a gripping, high-stakes first-contact science fiction adventure from the golden age of the genre. Set during humanity’s expansion across the stars, the story follows the crew of the starship Niccola as they confront the mysterious and technologically advanced Plumies—an alien species whose intentions are entirely unknown. When an unexpected encounter leads to a violent misunderstanding and the two ships become physically fused together in deep space, humans and Plumies are forced into an uneasy alliance for survival.