Rich quotations in Portable Text

// quote.js
export default {
  name: 'quote',
  type: 'object',
  title: 'Quote',
  fields: [
    {
      name: 'text',
      type: 'text', // <= This can also be a Portable Text field
      title: 'Text',
    },
    {
      name: 'author',
      type: 'string', // <= This could be a reference to an author document type, if you had that
      title: 'Author',
    },
    {
      name: 'url',
      type: 'url',
      title: 'URL',
      description: 'Source on the web', 
     }
  ]
}

// portableText.js
export default {
  name: 'portableText',
  type: 'array',
  title: 'Portable Text',
  of: [
    {
      type: 'block',
    },
    {
      type: 'quote',
    }
  ]
}

// portableText.jsx
export const serializers = {
  type: {
    quote: ({ node: { text, author, url } }) => {
      return (
        <figure>
          <blockquote cite={url}>
            {text}
          </blockquote>
          {author && <figcaption>{author}</figcaption>}
        </figure>
      )
    }
  }
}

// Query for documents with more than 5 quotes in them. Given the portable text field is named “body”
*[count(body[_type == "quote"]) > 5]{
  _id,
 _type,
 "quotes": body[_type == "quote"].text
}

// Query for documents that has a quote by "Ursula K. Le Guin”
*["Ursula K. Le Guin" in body[_type == "quote"].author]{
  _id,
  _type,
  "quotes": body[_type == "quote"].text
}