Bitcoin has broken above $52,000, but analysts at Swissblock are warning of an "imminent" pullback due to an unsustainable 33% rally over the past few weeks. However, 10x Research forecasts a target of $57,500 for the next upside.

- Bitcoin is up 10% for the week, outperforming the CoinDesk20 Index (CD20) with an 8% gain.

- The $52,000 area is a significant resistance level on long-term charts

- Possible pullback could be a buying opportunity if BTC holds support near $47,500

- 10x Research analyst Markus Thielen points to strong liquidity and growing demand for Bitcoin futures