Minor changes in documentation

tts.py

@@ -1,9 +1,16 @@
 """
-Text-to-speech synthesis (TTS)
+Text-to-speech synthesis (TTS) by using the FastSpeech2 model from fairseq S^2.
+This Python script convers an input text file in output wav file. The project
+was inspired by Dr. Tristan Behrens's arxiv-reader, which converts arXiv papers
+to audio. More details about the models and further examples are in the
+following sources. ↓
 
 Sources:
+— https://arxiv.org/abs/2109.06912
+— https://github.com/facebookresearch/fairseq/tree/main/examples/speech_synthesis
 — https://huggingface.co/facebook/fastspeech2-en-ljspeech
 — https://github.com/AI-Guru/arxiv-reader
+— https://www.linkedin.com/in/dr-tristan-behrens-734967a2/
 """
 import argparse
 from fairseq.checkpoint_utils import load_model_ensemble_and_task_from_hf_hub