Spring boot not serving static content returns a 404 not found

Spring boot configuration.

@SpringBootApplication
public class Application extends SpringBootServletInitializer {

    public static void main(String[] args) {
        ApplicationContext ctx = SpringApplication.run(Application.class, args);
    }

    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(Application.class);
    }
    ...
   }

Where I placed the necessary static content

And accessing it through my jsp

<link href="./resources/css/bootstrap.min.css" rel="stylesheet">

it returns a 404 not found. What am I missing?