Implementing SSML in module.exports with Alexa SDK Node.js + Lambda

At the moment I am trying to implement SSML into my Alexa Skill. With the external .js file containing the module.export function I am returning the data.

My index.js

const languageStrings = {
    'en-US': {
        translation: {
            MATERIALS: materials.MATERIAL,
        },
    },
};

External .js

module.exports = {
    MATERIAL: {
        'foo': '<speak>Lorem impsum dolor sit amet, consectetur adipiscing elit, "<emphasis level="strong">sed do eiusmod</emphasis>" ad minim veniam.</speak>',
    },
};

Somehow it gives me an error. How do I correctly implement this into my Skill that makes use of Node.js, Alexa-SDK and Lambda? Thanks in advance.

via Mae